Facade Construction Manual

Page 1


Facade Construction

Edition ∂


Authors Thomas Herzog Prof. Dr. (Univ. Rome) Dr. h.c. Dipl.-Ing. Architect BDA Technical University of Munich, Department of Architecture, Chair of Building Technology (until 2006) TUM Emeritus of Excellence Roland Krippner Prof. Dr.-Ing. Architect BDA Technische Hochschule Nürnberg Georg Simon Ohm, Department of Architecture, Research and teaching: Construction and Technology Werner Lang Prof. Dr.-Ing., M. Arch. II (UCLA) Architect Technical University of Munich, Department of Civil, Geo and Environmental Engineering and Department of Architecture, Chair of Energy Efficient and Sustainable Design and Building

Student research assistants: Simon Axmann, Lilly Brauner, Annika Ludwig, Verena Schmidt, Fabiola Tchamko, Ka Xu Authors of the 2004 edition: Dr.-Ing. Winfried Heusler (Aspects of building physics and planning advice) Prof. Dipl.-Ing. Michael Volz (Timber) Expert consultants for the 2004 edition: Prof. Dr.-Ing. Gerhard Hausladen, Dipl.-Ing. Stefan Heeß, Dr.-Ing. M. Sc. Reiner Letsch, Dr. Volker Wittwer

Expert consultant: Dr. Tilmann E. Kuhn

Research assistants (Chair of Building Technology) for the 2004 edition under the guidance of Prof. Thomas Herzog: Peter Bonfig (Surfaces – structural principles), Jan Cremers (External and internal conditions; Metal), András Reith (Natural stone; Clay), Annegret Rieger (Timber), Daniel Westenberger (Edges, openings; Manipulators)

Research assistant: Andreas Kacinari (Organisational support)

Student research assistants for the 2004 edition: Tina Baierl, Sebastian Fiedler, Elisabeth Walch, Xaver Wankerl

Editorial services Editing, copy-editing (German edition): Steffi Lenzen (Project Manager), Daniel Reisch Editorial assistants (German edition): Heike Messemer, Carola Jacob-Ritz, Eva Schönbrunner, Melanie Zumbansen Editors of the 2004 edition: Steffi Lenzen, Christine Fritzenwallner; Susanne Bender-Grotzeck, Christos Chantzaras, Carola Jacob-Ritz, Christina Reinhard, Friedemann Zeitler, Manuel Zoller

Reproduction: ludwig:media, Zell am See Printing and binding: Eberl & Kœsel GmbH & Co. KG, Altusried-Krugzell Publisher: Detail Business Information GmbH, Munich detail-online.com © 2021, third edition 2017, English translation of the second, revised and expanded German edition (2016) 2004, first German and first English edition

Drawings: Ralph Donhauser, Simon Kramer; Alexander Araj, Marion Griese, Martin Hämmel, Emese Köszegi, Dejanira Ornelas Bitterer

ISBN: 978-3-95553-369-4 (Print) ISBN: 978-3-95553-370-0 (E-Book)

Drawings for the 2004 edition: Marion Griese, Elisabeth Krammer; Bettina Brecht, Norbert Graeser, Christiane Haslberger, Oliver Klein, Emese Köszegi, Andrea Saiko, Beate Stingl, Claudia Toepsch

Bibliographic information published by the German National Library. The German National Library lists this publication in the Deutsche Nationalbibliografie (German National Bibliography); detailed bibliographic data are available on the Internet at http://dnb.d-nb.de.

Translation into English: Christina McKenna for keiki communication, Berlin

This work is subject to copyright. All rights reserved, whether the whole or part of the material is concerned, specifically the rights of trans­ lation, reprinting, recitation, reuse of illustrations and tables, broadcasting, reproduction on microfilm or in other ways and storage in data processing systems. Reproduction of any part of this work in individual cases, too, is only permitted within the limits of the provisions of the valid edition of the copyright law. A charge will be levied. Infringements will be subject to the penalty clauses of the copyright law.

Copy-editing (English edition): Matthew Griffon, Meriel Clemett for keiki communication, Berlin Proofreading (English edition): Stefan Widdess, Berlin Production & layout: Roswitha Siegler, Simone Soesters

This textbook uses terms applicable at the time of writing and is based on the current state of art, to the best of the authors' and ­editors' knowledge and belief. All drawings in this book were made specifically by the publisher. No legal claims can be derived from the contents of this book. This book is also available in a German-language edition (ISBN 978-3-95553-328-1)



Imprint Table of contents Foreword

4   5   6

Shell, wall, facade – an essay


Part A  The fundamentals


1  External and internal conditions 2  General basics of construction    2.1  Surfaces – structural principles   2.2 Edges, openings   2.3 Modular coordination 3  Aspects of building physics and planning advice

18  26  26  38  46  52

Part B  Structures built with specific materials  62 1  Natural stone 2 Clay 3 Concrete 4 Timber 5 Metal 6 Glass 7 Plastics

64  86 106 130 158 188 216

Part C  Special topics


1  Multilayer glass facades 2 Manipulators 3  Solar energy 4  Integrated facades 5  Refurbishing existing facades 6  Green facades

238 266 294 322 328 336

Appendix Authors Image credits Literature Statutory regulations, directives and standards Index

342 343 346 348 350 5


30 years after the publication of our first construction handbook, this is the first in the series to deal with facades. Over the centuries, architects’ design services have often concentrated on developing impressive section drawings of buildings, which frequently became objects of heated controversy over questions of style chosen as well as a medium for conveying new artistic ­positions. There is now an increasing focus once more on facades due to the growing importance taken on by exterior walls in the context of energy consumption issues and options for making use of environmental energy. In add­ ition to this focus, and usually contrasting with it, are efforts at self-promotion and “identifi­ cation with the address” for those clients for whom the “packaging” of their buildings, which often have quite banal interiors, has long since become a substitute for quality architecture. The booming Asian megacities show this quite clearly. The sequence of this book’s chapters takes an expedient approach to designing and developing facade structures. Aspects that apply generally to the exterior walls of buildings, involving demands made on them, their principal functionality and structural design, have been separated from descriptions of the special features of individual cases. The book represents more than just a collection of different buildings in various locations and contexts, of different types and technologies. Rather, specific features have been classified and described based on the various materials used in their walls or cladding. The first part deals with demands made on facades from the inside, which derive from the building’s usage type. Buildings face very different local climatic conditions, depending on the region in which they are located. Out of this confrontation arise the functional demands on an exterior wall. These are formulated as a remit that is initially open to a range of pos­ sible solutions, so implementation details are not described in this section. The book’s most important statements are made in the form of 6

images, diagrams and schematic illustrations showing the morphology of surfaces and openings. A building’s envelope interacts directly with its other subsystems: its support structure, the partitioning of rooms and technical building equipment. Various interdependencies exist or must be defined so that each structural system can be geometrically coordinated in the space. Dimensional and modular conditions and proportions must be defined for the building as a whole to be developed. Combining these aspects results in the parameters for material implementation based on the materials and construction methods to be chosen. If the materials and technologies used to manufacture them are important in defining further specific features, then certain physical, material, installation-related and aesthetic details must also be coordinated. The second part of this book’s structure is based on this context. Here the chapters have been kept separate from examples and precede them. Each begins with a brief summary of the history of civilisation’s use of the material and its specific features. Here we do not limit the area of materials applications to building construction, simply because as civilisation has developed, technology has often emerged in different ways and interactions with mater­ ials and initial applications have often emerged from very different areas. Stone, ceramics and metal, for example, are so significant that whole cultural eras have been named after them. Today too, much technical innovation comes from the construction industry, especially in modern facade construction, through a transfer of technologies from different sectors, such as forming technologies, surface treatments and robotics. These chapters are followed by a section showing a selection of built ex­­ amples focusing on materials, which provides insights into the range of possibilities available and is designed to inspire readers to further develop their own ideas. This is done by way of drawings of main facade details with explan­ ations provided in keys because this is the medium usually used for conveying information to architects.

We selected new projects with facades that interestingly embody the building as a whole, as well as “classics” that still set standards because of their architectural quality as well as a range of details that may be of practical value for architects and engineers working on older buildings. Projects are shown here not as whole buildings, rather our descriptions focus on their facades, which is why contributors other than architects, such as specialist engineers, are rarely mentioned in project descriptions, unless they played a major role in creating the facade. Readers will also notice that in describing ­construction details we have at times diverged from solutions or technical rules customary in Germany, as is justifiable in a book full of international examples. Those who would like more details on a project described are referred to the more detailed bibliographical references, which are indicated with a “º”. It may be regarded as valuable to depict a building as a large technical object, not as a complicated system, possibly unmanage­ able and consisting of many kinds of com­ ponents, but succinctly, simply, equally powerfully and sensitively designed. Developments in recent decades and enormously increased demands on building envelopes however, have led to the emergence of multilayer structures, each layer of which has specific functions. This is now a frequent feature of modern structures made of almost all materials, so structures made of specific materials and special facade construction topics are dealt with in separate chapters. A centuries-old principle of modifying and ­individually influencing the permeability of facade openings, whether for reasons of the building’s energy balance, interior climate, lighting conditions or safety, is dealt with under the chapter heading of “Manipulators”, which takes on a new topicality and covers a wide range of different types. We also take the view that the prevalence of multilayer and double facades in recent

­ ecades requires special mention and dis­ d cussion because there is still great uncertainty regarding their design and planning. Planners often simply follow fashionable trends instead of making good use of the main advantages of such structures. Basic errors are often made because there is not enough awareness of structural and energy technology interconnections or of individual variants available for possible use in construction. The integration of directly and indirectly operating solar systems in building envelopes is still uncharted territory for many and successful combinations of practical value, technicalphysical function, design and construction solutions are still the exception rather than the rule, even though the first pioneering applications were implemented decades ago. Munich, spring 2004 Thomas Herzog

For the second edition, Part B on “Structures built with specific materials” and the “Special topics” chapter have been revised and expanded to include examples from the past decade. New to this edition are three sections that do not deal mainly with specific materials but cover issues that have become increasingly important and need to be examined separately. The main reason for this are bioclimatic factors requiring special architectural solutions for the structural subsystem “facade” involving design in accordance with functional, technical and aesthetic criteria: refurbishment, the integration of annexed technical structural systems and the greening of exterior walls. It was therefore natural to develop a separate third section of the book covering these six areas. After a general description of remit and operating principles, it depicts a range of different solutions and renderings and various examples of built structures that represent the current state-of-the-art. Further developments are bound to follow, if only for reasons of efficiency, profitability and a commitment to sophisticated design. It is to be hoped that architects enthusiastic about the design of structural systems and components, people whose profession relies on an ability to comprehend the “technical organism” of a building as a whole, right down to the smallest detail, will continue to make cogent contributions to a broad “culture of construction” as a social imperative. The authors would like to thank all the people, institutions, architects, photographers and companies that have supported our work with their skilful contributions and everyone who worked on the new edition. Munich, summer 2016 Thomas Herzog, Roland Krippner, Werner Lang


Part A  The fundamentals

Sketch for the Schocken department store, Stuttgart (DE) 1929, Erich Mendelsohn

Whatever specific and very different facade designs may result from particular technologies and materials, there are also general rules and interdependencies that arise out of a building’s basic functions, the type of loads and stresses imposed on it, the logic of its structure and the way it fits together, its geometric order, options for using prefabricated elements and physical effects. These rules and interdependencies are overarching principles of general and fundamental significance, so we present them here before describing some completed buildings in detail.


External and internal conditions

11 h 11hh h h 11 11 11

13 h 13hh h h 13 13 13

ay 10 h M ayyaayy 10hh h h MaM 10 10 10 MM

7h 7hh h h 777

90° 90° 90° 90° 90° East East East East East

South-east South-east South-east South-east South-east

[Wh/m2d] 2 2 [Wh/m d] [Wh/m 2 d] [Wh/m d]2d] [Wh/m 5000 5000 5000 5000 5000

90° 90° 90° 90° 90°

South South South South South

South-west South-west South-west South-west South-west

West West West West West

60° 60° 60° 60° 60° 90° 90° 90° 90° 90°

2000 2000 2000 2000 2000

25° 18 h 25° 25° 25° 25° 18 h 18 h 18 h 18 h19 h 19hh h h 10° 19 19 19 10° 10° 10° 10°

45° 45° 45° 45° 45°

30° 30° 30° 30° 30° 0° 0° 0°0° 0°

3000 3000 3000 3000 3000

17 h 17hh h h 17 17 17

0° 0° 0°0° 0°

South South South South South

4000 4000 4000 4000 4000

16 h 16hh h h 16 16 16

Sep t eSpeetpt. SSeS ptp.. t.. Oct O . OO O ccttcc..tt.. Nov. N NN ovo.v. N Doevco..v. D D e e DeDcce..cc..

45° 45° 45° 45° 45°

50° 50° 50° 50° 50°

15 h 15hh h h 15 15 15

1000 1000 1000 1000 1000

[Wh/m2d] 2 2 [Wh/m d] [Wh/m 2 d] [Wh/m d]2d] [Wh/m 5000 5000 5000 5000 5000

90° 90° 90° 90° 90°

4000 4000 4000 4000 4000 3000 3000 3000 3000 3000 2000 2000 2000 2000 2000


1000 1000 1000 1000 1000



A 1.4




8 10 12 14 16 18 20 8 10 10 12 12 14 14 16 16 18 20 20 10 12 14 16 18 20 888 18 10 12 14 16 18 20 Hours of sunlight [h] Hoursof ofsunlight sunlight[h] [h] Hours ofof sunlight [h][h] Hours Hours sunlight

A 1.3  Diagram of the sun’s course (50° N) A 1.4  Solar radiation hitting south-facing surfaces pitched at various angles A 1.5  Solar radiation hitting vertical surfaces facing various directions A 1.6  Total solar radiation hitting wall surfaces pitched at various angles on sunny days at different seasons


A 1.5

Spring/Autumn Spring/Autumn Spring/Autumn S Spring/Autumn Spring/Autumn 800 S SSS 800 800 E W 800 800 E W WW 600 EEE W 600 600 600 600 400 400 400 400 400 200 200 200 200 200 0 8 6 10 12 14 16 18 20 04 000 8 10 4 666 6 888 10 12 12 14 14 16 16 18 20 20 10 12 14 16 18 20 444 18 10 12 14 16 18 20 Hours of sunlight [h] Hoursof ofsunlight sunlight[h] [h] Hours ofof sunlight [h][h] Hours Hours sunlight Winter Winter Winter Winter Winter 800 800 800 800 800 600 600 600 600 600 400 400 400 400 400 200 200 200 200 200 0 6 04 000 4 666 6 444

Total Totalradiation radiation[W/m [W/m22]22] 2 Total radiation [W/m ]] ] Total radiation [W/m Total radiation [W/m

Total Totalradiation radiation[W/m [W/m22]22] 2 Total radiation [W/m ]] ] Total radiation [W/m Total radiation [W/m

Summer Summer Summer Summer Summer 800 800 800 800 800 600 600 600 600 600 400 400 400 400 400 200 200 200 200 200 0 6 04 000 4 666 6 444

A 1.3

HH r irziz n HHooo orH irzizooo orniznnttaottalnlt aal l al

5h 5hh h h 555

Au Aug. AAuuA ggu..gg..

ch Mracrrhch araacrhch M M a MM Febr. eber.br. FFeFFber.br. . Jan ana.n. JJaJJna.n.

8h 8hh h h 888

6h 6hh h h 666

14 h Ju ly 14 14hh h h JJuuJJluuy ly 14 14 ly ly

ril Arpilril pil ril p Arp AApA

9h 9hh h h 999

60° 60° 60° 60° 60°


JJ JuuJnuuenJu nenee ne

Facades’ performance potential 12 h 12hh h h 12 12 12


A facade should be able to meet the requirements resulting from the climate as much as possible. Adopting this approach can ­minimise or avoid the need for additional measures, such as further technical equipment, to control the interior climate. Know­ ledge of the relevant basic physical principles involved is indispensable in achieving this planning goal. Supplementary direct-acting measures can support such functions on both sides of the facade. Other structural elements inside the building can also be “activated” to do this, by storing energy in walls and ceilings, for example. Open areas of water outside or in interstices can be used for cooling (by evaporation) or dehumidification (if there is a sufficient difference between the temperature of the water and of the air in the room), and appropriate measures can make use of energy generated during peak periods. Solar radiation, from which buildings need protection, can be turned into electricity by means of photovoltaic modules or absorbed by collectors and used to heat water. High outdoor temperatures, wind and rain can also be made use of (see “Solar energy”, p. 294ff.). Remaining requirements that cannot be ad­­ equately met through structural measures must be met by technical systems providing tem­ perature control, lighting, air purification, a ­sufficient exchange of air or humidification or ­dehumidification. Such supplementary tech­ nical measures always require additional energy as well as costly and complex transport of media and maintenance. If technical equipment of this kind is directly integrated into a facade, it is referred to as an “integrated facade” (see p. 322ff.). Equipment housed not in the building’s technical centre but in the facade, at the point where it is required, is referred to as “facade-integrated decentralised building technology” [1]. Apart from external factors, other conditions imposed by the overall structural context must be taken into account, including the coordination of dimensions (see “Modular ­coordination”, p. 46ff.), structural interdependencies, necessary tolerances and installation sequences – topics that will be dealt with in subsequent chapters. External conditions: solar radiation


8 10 12 14 16 18 20 8 10 10 12 12 14 14 16 16 18 20 20 10 12 14 16 18 20 888 18 10 12 14 16 18 20 Hours of sunlight [h] Hoursof ofsunlight sunlight[h] [h] Hours ofof sunlight [h][h] Hours Hours sunlight A 1.6

The sun is one of the most central and essential of all site-specific external conditions. It is our greatest direct and indirect energy source and makes all life possible. The amount of energy that it sends to the Earth is about 10,000 times what humanity’s global energy requirements were in 2010 (an average

External and internal conditions

1,353 W of energy hits every square metre of the Earth’s outer atmosphere). For human ­purposes, this is an infinite, cost-free and ­environmentally friendly source of energy. To make use of solar energy in a building, it is essential to consider the intensity and dur­ ation of the radiation on its surface, depending on its facade’s orientation and inclination. In planning facades, the following related factors and interdependencies must also be taken into account if solar radiation is to be made use of: •  The course of the sun, depending on the location and time of day and year •  Solar radiation levels, depending on the ­surface’s orientation and inclination, location, time of day and year and weather •  Various kinds of solar radiation (diffuse, direct and different wavelengths) and their quantitative ratio depending on the weather, direction, location and time of day and year •  Interactions with surfaces and materials •  Relation to heating requirements based on planned usage

kWh/m2 Global solar radiation/per annum (energy) 5 Available solar radiation 4 3 2 Diffuse solar radiation

Heating requirements



























A 1.7






A 1.8

70 °C 65 °


60 °


55 °

1  Black (high gloss) 2  Dark blue


50 ° 45 °

3  Brick red 4  Ivory


5  Opaque white

40 °

Figures A 1.3 – A 1.11 show a selection of the main factors involved

Direct solar radiation


35 °

6  Outside air

30 °

The following solar radiation figures can be used as a basis for Germany [2]:

25 °

,300 –1,900 hours of sunlight / year 1 750 –1,250 hours of sunlight / heating limit 15 °C 500 – 950 hours of sunlight / heating limit 12 °C 400 – 775 hours of sunlight / heating limit 10 °C

15 °


20 °

10 °

Hours of exposure to sun of a southwest-facing facade

5 °

Amount of heat = 330 cal/cm2 22.06.1963

0 °

23.06.1963 A 1.9

The proportion of diffuse radiation of all radi­ ation accruing over a year is approximately: South-facing facade 30 % East and west-facing facade 60 % North-facing facade 90 % (Difference from 100 %: direct solar radiation)





Solar radiation can also be hazardous for ­ eople (overheating, premature skin ageing, p skin cancer), who may need suitable protection from it. Thermal comfort  The various demands on internal climatic conditions can be summed up by the term “thermal comfort”. Among the main factors influencing these demands that are connected with the facade, are (Fig. A 1.12): •  Temperature of the air in the space (a) •  Relative humidity in the space (b) •  Surface temperature of structural components adjoining the space (c) •  Air flows reaching the body (d)

A 1.11

A 1.10        over   1,175 1,150 –1,175 1,125 –1,150 1,100 –1,125 1,075 –1,100 1,050 –1,075

1,025 –1,050 1,000 –1,025      975 –1,000      950 –  975   under 950

A 1.7   Heating demands / duration of sunshine ­(schematic diagram) A 1.8   Daily average intensity of solar radiation in ­central Germany (50° N) A 1.9   Temperatures measured on a sunny day on the surfaces of south-facing facades of different colours A 1.10  Local distribution of annual global radiation [kWh/m2] in Germany A 1.11  Projection diagram principle of the sun’s course




Surfaces – structural principles

The principle of double sealing is that a first external seal prevents water on the surface from penetrating and a second seal, perhaps with a hollow-chamber profile, stops air from flowing through. Turbulence in the interstice (e.g. in labyrinth form) reduces wind pressure and any water that has penetrated can run off. Installation sequences

Two general principles govern the installation and dismantling of joints based on overlapping principles: •  Individual elements can only be installed in a certain strict order and must be disman­ tled in precisely the opposite order. Individ­ ual elements in such a chain can only be exchanged with some restrictions and sub­ sequent damage (e.g. of sealing elements or rebates). Special solutions may be required for joining and sealing reused or refitted structural components (e.g. in Fig. A 2.1.13, p. 33 “tongue and groove” and “grooved” components). •  There is no fixed sequence for installing and dismantling individual structural compo­ nents. Elements in the same system can be replaced (e.g. in Fig. A 2.1.13, p. 33 “gap ring”, “cover profile” and “sealing compound” joints). This is especially recommended if there is a risk of damage (e.g. in the plinth zone) and an element has to be replaced. From monolithic to multilayer / multi-shell

Homogeneous shell structures made primarily of just one material (often referred to as mono­ lithic) are unlikely to meet the current increased thermal insulation demands made on building envelopes. Planners can precisely adapt a facade’s ­performance profile to meet certain require­ ments by creating differentiated structures that assign individual functions to different ­layers with a specific material and structure. Making layers or shells modifiable allows the building envelope’s properties to adapt to ­periodically changing external conditions. ­Individual layers and shells can be subse­ quently added or replaced, making it possible to adapt the building envelope to differing requirements during its use. This means that an outer weatherproof shell designed to be a “wearing course layer” can be renewed after a period of use without the underlying struc­ ture having to be changed. This principle can also be useful in subsequent retrofitting for renovating and optimising existing exterior wall structures. Assigning individual functions to layers and shells may, however, also have disadvantages depending on quality of the materials and con­ struction methods chosen: •  Creation of lots of interfaces between differ­ ent materials and structural components with the risk of material incompatibilities •  Increased number of joints and therefore of potential weak points 34

•  Creation of uncontrolled cavities •  Attachment problems: penetration of waterbearing or insulating layers, creation of bending moment in the anchoring of facing shells •  Greater cost and effort involved in manu­ facture •  Greater maintenance cost and effort •  Building a wall may involve several trades and responsibilities, which can increase the cost and effort involved in coordinating them and result in overlapping liabilities •  Problems in separating and thus disposing of individual layers The following tendencies are currently pre­ dominant: •  Increasing performance of functional layers •  Reducing the space required for layers (e.g. vacuum insulation) through to miniaturising of functional structures (e.g. prismatic light deflection systems less than 0.1 mm high) •  Surface coatings using nanotechnology •  Combination of several functions in a single polyvalent layer

Typical structures and how they work

Figure A 2.1.15 shows a selection of schematic representations of structures classified accord­ ing to functional and structural criteria (see also “Classification of design solutions”, p. 27f.). The number and thickness of the layers and shells vary greatly. They can be divided into solid and lightweight structures and are suit­ able for temperate climate zones. Protection from driving rain Moisture-absorbing materials require protec­ tion from frost, and any moisture that may pene­ trate must be able to periodically completely evaporate. Facade water can be drained off through various layers. Some facade water will run off down the back of the cladding of venti­ lated weatherproof shells with open joints. This reduces the risk of soiling since less dirt is deposited on horizontal surfaces because it is regularly washed off. Windproofing Facades usually need to be windproof. The inner facade layer of a multilayer facade must be windproof, as must joints with other struc­ tural components.

The functions of layers and shells

The following functions (often also combined) can be allocated to individual layers or shells, e.g.: •  Visual effects, information media •  Mechanical protection •  Protection from driving rain • Windproofing •  Blocking /restricting of vapour permeability •  Light refraction and diffusion •  Reflection of light radiation and thermal ­radiation •  Absorption of thermal radiation •  Reflection of electromagnetic radiation •  Absorption of sound •  Reflection of sound •  Heat storage •  Reduction of heat transition •  Transfer of loads •  Discharge of heat •  Absorption and release of water vapour •  Conversion of solar energy into thermal or electrical energy Other layers may be formed based on struc­ tural requirements, e.g.: •  Release of water vapour •  Discharge of condensation or surface water •  Balancing out unevenness •  Layers for material-bonded joints (adhesive layers) •  Measures for stabilising layers (e.g. prevent­ ing thermal insulation layers from swelling) •  Substructures for connecting layers and shells •  Separating layers that are required because of materials incompatibilities •  Sliding layers allowing for unrestrained movement

Thermal insulation Material layers that trap a large proportion of stationary air guarantee good insulating prop­ erties. Open-pored insulating materials that can absorb moisture and water through capil­ lary action, which greatly impairs their func­ tioning, must be effectively protected from moisture. Water vapour diffusion The water vapour diffusion resistance of layers must generally diminish from the inside to the outside to prevent condensation from forming in a structural component (and avoid steam traps). Condensation that collects in wall struc­ tures during the heating period must be able to evaporate completely in warmer seasons. Rear ventilation Effective rear ventilation of a facing shell requires a distance of at least 20 mm between cladding and shell and adequate ventilation openings of at least 50 cm2 for every metre of wall length [8] to efficiently release moisture (infiltrated facade water and/or condensation) and heat (in summer). Layers of stationary air (no rear ventilation) have an additional insula­ tion effect. Heat storage Inside layers with good heat storage capacity can be activated to help regulate the interior climate. Sun shading Sun shading devices that reduce the input of energy through layers that are permeable to solar radiation are most effective mounted outside. Their rear ventilation counteracts the

Surfaces – structural principles

Not permeable Not modifiable

Not permeable Not modifiable

Not permeable Not modifiable

Not permeable Not modifiable

Not permeable Energy producing Modifiable

Load-bearing or non-load-­ bearing Single-layer Single-shell Not rear-ventilated

Load-bearing or non-load-­ bearing Multilayer Single-shell Not rear-ventilated

Load-bearing or non-load-­ bearing Multilayer Double-layer Not rear-ventilated

Load-bearing or non-load-­ bearing Multilayer Double-shell Rear-ventilated

Load-bearing or non-load-­ bearing Multilayer Triple-shell Rear-ventilated (outermost shell)

Material structure determines performance; can only be ad­ justed by changing the wall thickness; any moisture that has penetrated must be able to peri­ odically completely evaporate

Improved insulation due to the insulation layer; inner and outer wear and protective layer; heat storage capacity can be used to heat the interior

Robust external shell provides physical protection for the insu­ lation layer and against driving rain; outer and inner shells may be partly connected, but do not form a structural unit

Facing shell can be exchanged; mounting may not be allowed to impede rising airflows; con­ densation and any penetrating moisture are safely extracted; ventilation openings required

Rear-ventilated shell made of light-deflecting louvres; trans­ lucent shell with transparent ­insulation in front of a solid ab­ sorber; overall structure opaque; energy production modifiable and can be regulated with con­ trol circuit technology

Not permeable Not modifiable

Not permeable Not modifiable

Permeable (light) Not modifiable

Permeable (light) Not modifiable

Permeable (light) Modifiable and regulated

Load-bearing or non-loadbearing Multilayer Single-shell Not rear-ventilated

Load-bearing or non-load-­ bearing Multilayer Double-layer Rear-ventilated

Non-load-bearing Single-layer Single-shell

Non-load-bearing Single-layer Double-shell Rear-ventilated or not rear-­ ventilated

Non-load-bearing Multilayer Single-shell

Lightweight structure; inner and outer layer usually joined to form a structural unit; vapour trap pre­ vented by a barrier on the inside; as stud wall also part of the loadbearing structure; sandwich structures are a special case

External, rear-ventilated wear and protective layer; diffusion resistance declines towards the outside; separate wind ­protection layer; inner lining is a separate layer

The structure itself is not energyproducing, even though it is permeable to solar energy, which is absorbed by structural components in the interior; no insulation

Low level of insulation because air circulates in the cavity (heat losses due to convection); shells do not form structural unit; risk of condensation form­ ing in the cavity

Functional unit made of several translucent or light-refracting ­layers, with reflecting layers if ­required; permeability to light can be modified

Permeable (to light) Modifiable

Permeable (light) Modifiable

Permeable (light and air) Modifiable

Permeable (light) Not modifiable

Permeable (light) Not modifiable

Non-load-bearing Multilayer Single-shell

Non-load-bearing Multilayer Double-shell Rear-ventilated

Non-load-bearing Multilayer Four-shell Rear-ventilated

Non-load-bearing Multilayer Single-shell

Non-load-bearing Single or multilayer Double-shell

Good thermal insulation due to two stationary layers of air / inert gas and possibly reflective coat­ ing (Low-E); adjustable or fixed louvres as rear-ventilated facing shell

Double facade, outer and inner glazing; openable, air cavity ­between shells has controlled ventilation, louvres and glare protection on the inside; separ­ ate shell for regulating per­ meability to light

Pneumatic structure with trans­ lucent layers that form a single structural unit, depending on the system, i.e. a single-shell structure

Membranes as two structurally separate shells; layer of air or controlled ventilation for extract­ ing water vapour and heat; but there are heat losses due to convection

Functional unit made of several translucent layers; improved ­insulating due to thermal insula­ tion; permeability to light can be modified and is self-regulat­ ing, with thermotropic glass, for example

Opaque material structure

Translucent material structure

Opaque thermal insulation

Translucent thermal insulation

Light-refracting system

Rear ventilation


Vapour barrier

Reflection of radiation

Light refraction, glare protection

A 2.1.15  Structures /assemblies of ­layers and shells perpendicu­ lar to the plane of the facade, left: outside


Aspects of building physics and planning advice

Thermal insulation functions

Structural functions

Physiological functions

Ecological ­functions

Economical ­functions

Hygienic functions

Comfort-related functions

Preventing damage from condensation

Preventing mould formation

Protection from excessive cooling and overheating

Minimising usagerelated energy ­consumption

Minimising energy costs (heating and cooling costs)

Preventing damage due to diffusion

Reducing dust formation and vortices

Reducing interior air speeds

Extending the building’s functional and service life

Extending the building’s service life

Preventing constraining stresses

Adapting and ­harmonising the ­temperatures of wall surfaces inside rooms with the rooms’ air ­temperature

Minimising the investment and operating costs of air-conditioning systems

A 3.2

0.15 W/m2K, even good triple insulating ­ lazing, inert gas-filled glazing or vacuum g ­insulating glazing has U-values of around 0.6 W/m2K. In other words, nowhere near the thermal values of the well-insulated exterior walls made of opaque building materials men­ tioned above. Standard commercially avail­ able window frames may well have U-values of > 1.0 W/m2K, so thermal weak points can easily develop around them. In joining window frames or frame profiles in glass facades to solid walls, details should be appropriately constructed to ensure that thermal resistance is as consistently effective as possible at every point in the facade to ­prevent thermal bridges and the risk of con­ densation forming. Planners should consider factors such as heat transmission, convection and the exchange of long-wave radiation in choosing the properties of materials, structural components and connections. This is espe­ cially important in and around joints, at the bonded edges of glazing and panels, and in the area of fastening elements because linear or intermittent thermal bridges and leaks can increase the risk of heat losses, condensation and mould formation. Horizontal and vertical corners, inside and out, attics and footings, and projections and recesses in insulating and sealing layers are in practice particularly critical, especially at junctions between different types of facades and structures. Mistakes made in planning or construction 54

can greatly impair the function and durability of structural components, increase heating energy consumption, have negative ecologic­ ­al effects and be harmful to one’s health if mould forms. Protection from moisture

Exterior weather factors such as precipitation and fluctuating extremes of temperature make intensive demands on facades, which are also exposed to considerable loads from moisture hitting the splash water zone of the building’s plinth, damp from surrounding soil and humid­ ity inside the building. Water must not be allowed to penetrate struc­ tures in and around closed facade surfaces (such as plastered masonry), punctuated facades and partitioned exterior wall struc­ tures (like glass facades). Any water that does penetrate must be extracted in a controlled manner. The moisture content of materials sensitive to damp, such as certain insulating materials and timber, must also be kept low. As well as choosing adequate materials, plan­ ners must make every effort to prevent ther­ mal bridges in building facades because they are usually also weak points in terms of mois­ ture and can pose an increased risk of con­ densate forming on interior surfaces and inside the facade. The permeability to vapour of individual com­ ponents and the application of sealing meas­ ures in and around joints and fastening elem­

A 3.2  Thermal insulation functions A 3.3  Facade with roller blinds (inside) and louvre system outside, Munich (DE) 2001, Peter C. von Seidlein

ents will determine the risk of condensate forming inside exterior walls. Effective prevention of condensation is a fun­ damental precondition for ensuring both a facade’s durability and a healthy interior cli­ mate. We now know that mould can form even in the absence of visible condensate, resulting in critical surface temperatures being redefined in DIN 4108-8. The basic rule of construction in Central Europe is that the inside of a building should be more vapour-proof than the outside. This basic rule is reversed for warm, damp ­climates, where the outside should be more vapour-proof than the inside. Condensate can form in multilayer glass facades when moist air inside cavities of the facade meets cold surfaces. The risk of this occurring can be reduced by improving the quality of insulation between exterior layers and ventilating the cavities [5]. The demands on a facade’s moisture protec­ tion depend largely on the building’s usage and technical equipment. Air in indoor swim­ ming pools (and in winter in air-conditioned buildings generally), for example, is more humid, increasing the risk of condensate ­forming. One phenomenon often overlooked in planning is the formation of condensate or hoar frost on a facade’s exterior surface. This risk increases with the quality of insulation and is especially great with highly insulating panels and triple glazing, whose exterior surfaces barely warm up at all due to these units’ low heat transfer.

Aspects of building physics and planning advice

The result is that the steamed-up glass surface hardly dries under cold weather conditions. This phenomenon will become increasingly common in future. Sun protection

After thermal insulation, protection from over­ heating is one of a facade’s most important functions. This is crucial not only in tropical and subtropical climate zones but also in ­temperate climates like Central Europe’s because of changing climatic conditions and users’ increasing comfort requirements. Plan­ ners need to find a balanced relationship between the glazing percentage or type of glazing and the sun-shading system to provide a consistent overall solution. The intensity of solar radiation on “permeable” (or transparent) facade surfaces is more or less transient due to changing solar radiation levels and geometric variables in and around building openings. Relevant for an adequate and consistent supply of daylight is the build­ ing’s specific geometry, with its projections and recesses, and the dimensions, distribu­ tion, orientation and angles of transparent or translucent facade components. The illumin­ ation of interiors by daylight, thermal loads from solar radiation, and visual contact with the ­outside are influenced by the size, orientation and position of openings in the facade, by radiation’s physical characteristics and by the photometric properties of glazing. This also applies to added components such as sunshading devices and anti-glare screens and to deflected daylight (Fig. A 3.3). Sun protection systems The primary function of sun protection systems is to prevent overheating and ensure a com­ fortable interior climate. They also greatly influ­ ence the resulting energy consumption used in cooling, which accounts for a large propor­ tion of power consumption in tropical and subtropical climate zones. Solutions are required that ensure an adequate supply of daylight in the interior without overheating it. This can be achieved by blocking out direct sunshine as far as possible, while diffuse daylight can be transmitted into an interior as necessary to illu­ minate it. Sun shading systems can be classified into fixed or moving systems. Fixed components are structural components that can project from an exterior wall, be freestanding or consist of fixed louvres (see Fig. A 2.2.8, p. 42). Moving systems, such as roller blinds and folding shut­ ters, are dealt with in detail in the chapter on “Manipulators” (p. 266ff.). One advantage of fixed systems is that they require little maintenance. The sun’s position constantly changes over the course of the day and the year in a defined way, so fixed systems occasionally let some direct sunlight through. Some solar radiation may, however, be blocked out, which can reduce light in the interior.

Moving systems, in contrast, are almost ideal. They can immediately react to the weather, and with the use of appropriate components, incoming daylight can be reflected onto a room’s ceiling, where the reflected light can provide even illumination into the depths of the space. The sun protection and light refraction effect of adjustable louvre systems can be optimised if: •  The pitch angle of louvres covering upper windows and areas of window users look through is adjustable •  The topsides and underside of louvres have different degrees of reflectivity •  Louvre surfaces have a geometric structure Common perforated louvre systems (e.g. blinds or shutters) generally transmit slightly more radiation and increase cooling loads ­marginally compared with non-perforated ­systems with similar structures and surfaces. Systems that do not completely block out direct sun may require appropriate anti-glare screens. What is essential for a facade’s sun protection effect is not just the type of sun ­protection used, but also its position. It is important to ensure that sun protection is attached outside the glazing. In windy locations in particular, stable construction of moveable sun protection systems is crucial in ensuring their protective function when there is both sunshine and wind. Glare protection

External interference should not be allowed to impair visual function and comfort. The dis­ tribution of luminance in a user’s field of vision and resulting contrasts are decisive in en­­ abling them to recognise objects and for the occurrence of glare and absolute levels of luminance. A distinction is made between physiological glare, which directly impairs vision, and psychological glare, which can cause premature fatigue and adversely affect performance and well-being. Direct glare is directly caused by a light source, while reflected glare is the result of reflections from light surfaces onto shiny sur­ faces. The crucial variables for direct glare are the observer’s visual angle relative to their environment and the luminance perceptible in the viewing direction. The brighter the envir­ onment is, in a tolerable range, the lower the risk of glare is. The low luminance of computer monitors (10 –100 cd/m2) means that rooms with com­ puter workstations are subject to increased requirements for glare-free interior illumination. For this reason, windows in such rooms must be able to be completely screened against direct sun-light and its associated heat radi­ ation and glare. Appropriate measures should be taken to prevent glare from reflecting off ­surfaces the sun shines onto. These demands are constant, even in the face of strong wind,

A 3.3


Part B  Structures built with specific materials

Anyone involved in planning and building facades in compliance with generally accepted rules will at some point need to make decisions on materials. This entails making targeted use of the properties of existing construction materials and of those that may need to be developed as well as taking them into account in planning and construction. Architects face a series of guidelines, considerations, recommendations and ideas with a local or regional or sometimes even a global background that are of a functional, economic, ecological and/or cultural nature and arise out of planning and approvals law constraints, rules, standards and regulations. A facade is one subsystem in the wider system of the “building”, a large and complex technical object whose use of materials determines phases in its production in a workshop or factory, its composition of elements into structural components, and its transport, assembly and installation in both intermediate and final states. This means that a building's subsequent mainten­ ance and upkeep, operation and options for exchanging parts must all be well thought out in terms of the spaces, organisation and effects on structural details involved.

Wrapped Reichstag, Berlin (DE) 1995, Christo & Jeanne-Claude

A knowledge of the structural, physical and technical features of the building materials involved and of the construction, technology and manufacture of structural elements and components, taking the structure’s special characteristics and technical context into account, are among the essential skills required of architects responsible for designing buildings. The following examples are designed to provide them with guidance and orientation in their work. 63


B 3.2

formwork and powerfully highlight the material of the facade and interior. One building in which concrete was expertly used in the facade’s modelling is the Goethe­ anum in Dornach (1928) by Rudolf Steiner, although building such plastic, organic designs involves a great deal of work and sophisticated artisanal formwork techniques.

B 3.3

B 3.4

B 3.5


In the 1950s concrete became a mass-market building material, used in all kinds of con­ struction tasks. One main driving force was Le Corbusier, who sought to highlight concrete’s immediate, “raw” materiality – “Béton brut”. He used it skilfully as a design medium in relief and /or plastic facade surfaces, such as the Sainte-Marie-de-la-Tourette priory (1960) in Éveux near Lyon (Fig. B 3.2). While Swiss firm Atelier 5 used raw exposed concrete for (small) residential buildings in building the Halen housing estate near Bern (1961), Louis Kahn chose very smooth surfaces for the Jonas Salk Institute in La Jolla (1965). Kahn was also the first to structure concrete facades along orthogonal lines by using shadow joints and carefully positioning formwork ties, making the facades’ production process legible. In the 1960s and 1970s many architects increasingly used the options concrete offered for moulding exterior walls and buildings and the various design possibilities of its surfaces. Unique buildings from this period include the Pilgrimage Cathedral in Neviges (1968) and the Town Hall (Rathaus) in Bensberg (1969) by Gottfried Böhm. These buildings – especially the church – model a plastic, rugged structure with powerful, opaque surfaces whose fine texture of formwork structures prevents them from appearing monotonous (Fig. B 3.3). Another very plastic use of concrete as a ­material is evident in an office building by Barbosa & Guimarães Arquitectos in Porto (2009) (Fig. B 3.5). Here polygonal facade surfaces determine not only the building’s outside appearance but also its interior spaces. While Carlo Scarpa explored concrete’s mouldable qual­ ities in an almost (skilled) craftsmanly manner, especially in the Brion family monument in San Vito d’Altivole near Asolo (1975), Paul Rudolph

used industrial textured formwork for the Art and Architecture Building at Yale University in New Haven (1958 – 64) (Fig. B 3.1, p. 107). The fluted profiling of its coloured surfaces, alternating smooth grooves with rough, broken piers, creates a sophisticated play of light and shade. Adding locally available materials to concrete and/or structuring damp surfaces can open up further design options, as Auer + Weber demonstrate in their ESO Hotel at Cerro Paranal (2001) (see p. 123) and Herzog & de Meuron at the “Schaulager” art storage facility in Basel (2003) (Fig. B 3.8). More recently architects have often sought to express the impression of a monolithic construction method, down to the last detail. The avoidance of any construction joints, dispensing with visible formwork ties, and structural components with extremely pared-down cross sections and novel appearances has subjected this high-performance material to enormous technical challenges. Prefabrication

Producing concrete on a building site has structural and technical disadvantages, so efforts have been made to break structures down into similar, transportable elements that can be serially produced in prefabrication plants. These make it possible to work in any weather and ensure higher quality and greater precision in production and higher standards in surface finishes. The first field factory for precasting concrete elements opened in France in the early 1890s. In 1896 French stonemason François Hennebique made the first building prefabricated in a series, using a transportable cubicle made of 5 cm thick, reinforced concrete slabs. From 1920 assembly-based construction methods using steel-reinforced concrete became increasingly important. Architects like Ernst May, who applied a system of wall blocks of various sizes that he developed in a series of housing estates in Frankfurt am Main (Praunheim, 1927), and Walter Gropius, who used a small-format construction method and hollow slag concrete blocks for the Dessau-Törten estate (1927), worked on con-


B 3.6

cepts involving extensive prefabrication. Although these systematic approaches did not become established in construction technology or economy, these experiments were an important (first) step on the path to indus­ trialising building [2]. In the 1950s and 1960s large panel construction – building with large format, load-bearing walls – became widespread. While prefabricated system construction resulted in the building of very schematic facades on a massive scale, postmodern architecture almost reversed this approach, using prefabrication and the plastic malleability of concrete elem­ ents to create arbitrary interplays of colours and forms. Architects like Angelo Mangiarotti (see p. 116), Bernhard Hermkes (Architecture faculty building at the Technische Universität Berlin, 1968, Fig. B 3.4), Gottfried Böhm and Eckhard Gerber formulated architectural responses. Böhm’s administration building for Züblin AG in Stuttgart (1984) shows a sophisticated treatment of the forms and colours of precast elements. Gerber used orthogonal planar steel-reinforced facade elements in a structurally clear way to clad the columns and spandrel panels of an office building in Dortmund (1994). “Heavy-duty prefabrication” is once again an option from a technical and design point of view. Architects such as Thomas von Ballmoos, Bruno Krucker (Stöckenacker housing estate in Zurich, 2002) and Léon Wohlhage Wernik (Sozialverband headquarters in Berlin, 2003) have planned buildings with storey-high, multilayered precast elements that vary slightly in size and create a harmonious result.

B 3.2  Priory of Sainte-Marie-de-la-Tourette, Éveux (FR) 1960, Le Corbusier B 3.3  Pilgrimage Cathedral, Neviges (DE) 1968, Gottfried Böhm B 3.4  Architecture faculty TU Berlin (DE) 1967, Bernhard Hermkes B 3.5  Vodafone Headquarters, Porto (PT) 2009, Barbosa & Guimarães B 3.6  John Storer House, Hollywood (US) 1924, Frank Lloyd Wright B 3.7  Office building, Centraal Beheer, Apeldoorn (NL) 1972, Herman Hertzberger B 3.8  Schaulager, Basel (CH) 2003, Herzog & de Meuron

One form of unreinforced facade cladding is small-format, concrete artificial stone panels. Panels fixed with mortar are a robust, easilyworked building material that has been used in construction for more than 100 years, especially at the bases of buildings. One of the ­earliest examples of this in Germany was the Town Hall (Rathaus) in Trossingen (1904), where concrete panels clad the plinth and splayed door jambs. The wide range of ways that concrete can be worked and shaped and the combinations of different aggregates possible have been used to create orna­ mental structural elements such as (demi-) ­columns, balusters, gables, rosettes and the like. Concrete panels are now widely used as a suspended, rear-ventilated, small-format cladding material, as in the red facade of the German School in Beijing (2001) by Gerkan Marg + Partner. Concrete blocks

Concrete blocks offer the advantages of en­­ abling small-format, light construction with a wide range of colours and surface treatments. From 1914 Frank Lloyd Wright explored various ways of using them. With his “Textile Block”

B 3.7

system, he was seeking an alternative to largeformat panel construction. Starting from a square basic module, he worked with variously shaped bricks and stones. Buildings like his John Storer house in Hollywood (1923) feature richly ornamented facade surfaces with alternating patterns of smooth and structured stones (Fig. B 3.6) [3]. Egon Eiermann focused on the motif of a translucent wall, using concrete grid blocks with (coloured) glass infills in the St Matthew Church in Pforzheim (1956), and the Kaiser-Wilhelm Memorial Church in Berlin (1963). Another application for exposed masonry blocks is as opaque surface filling in a steelreinforced concrete structure, a technique frequently found in Herman Hertzberger’s work. In buildings such as the Centraal Beheer office building in Apeldoorn (1972, Fig. B 3.7), the Vredenburg music centre in Utrecht (1978) and the Apollo Schools in Amsterdam (1983), untreated exposed masonry, visible inside and out, with its the slightly porous surfaces and variously coloured textures, contrasts strikingly with smooth exposed concrete and glass (brick) surfaces [4].

B 3.8



B 7.6

Pneumatic structures In 1948, Walter Bird designed the first air-filled pneumatic structure to protect sensitive radar equipment. Based on his design, pneumatic structures were further developed for civilian uses, such as roofs over swimming pools and tennis courts. Buckminster Fuller caused a furore in 1950 with his proposal to build a dome over Manhattan (Fig. B 7.6) [2]. In 1959, Frei Otto started work with Kenzo Tange on plans to roof over residential complexes in the Arctic. These developments peaked in 1970 at the World Expo in Osaka, which resembled an exhibition of the possibilities for pneumatic structures available at that time [3]. Tent structures From around 1950, Frei Otto worked intensively on further developing applications for tensile-stressed structures, which until then had been almost exclusively produced from natural materials (Fig. B 7.7) [4], and laid the foundations for the use of plastics in such structures. Synthetic fabrics and films are now among the leading materials used to build tent structures due to their outstanding material properties. Plastics manufacture

B 7.7

Plastics consist of materials that do not exist in nature in their final form. They are usually made from petroleum-derived products and their main characteristic is a macromolecular structure. Plastics are made in a controlled chemical reaction in which hydrocarbon ­molecules are split and recombined to form long macromolecules in the following processes [5]: • Polymerisation • Polycondensation • Polyaddition Classification of plastics Whatever process is used to make them, the macromolecules of plastics can be structured in long molecular chains, be ramified or form a network. The following types of plastics are differentiated based on their degree of cross-linking (Fig. B 7.9): • Thermoplastics • Elastomers •  Duroplasts or thermosetting plastics

­ olyethylene and polypropylene are also p often used. Plastics have become important in construction because of their advantageous properties for individual applications: •  Sufficient compressive and tensile strength, rigidity, hardness and wear resistance •  High levels of transparency •  Can be coloured in shades ranging from crystal clear through to black •  Adequate to outstanding resilience •  High elasticity •  Low density •  Satisfactory temperature resistance •  Good electrical insulation properties and low thermal conductivity •  Weather resistance •  Low water absorption •  Highly resistant to chemicals •  Easy to process and work •  Very good surface qualities •  Surfaces can be painted The material properties of plastics can be extensively modified by changing the manu­ facturing process and formulation used to make them so that construction materials with the same designation can be designed in ­various ways to meet specific requirements. With regard to their resistance to ageing, it should be noted that many plastics products are much younger than the life expectancy of buildings. This aspect should be particularly taken into account in planning building elem­ ents that are highly exposed to various risks, such as facade elements and roof seals. Reaction of plastics to fire

Fire safety properties become especially important when plastics are used in and around a building envelope. The main criteria here are: • Flammability •  Ignition temperature •  Disintegration temperature •  Smoke and gas formation •  Toxicity of decomposition products •  Corrosion caused by decomposition p ­ roducts As well as producing highly toxic gases, the smoke caused by fire can greatly impede visibility, so the choice of a suitable plastic must depend on its potential toxicity and smoke release. Decomposition products from smoke may also have a very corrosive effect on other materials. Flammability can be reduced by using a fire retardant.

Material properties Semi-finished products for exterior walls General characteristics

B 7.8


The construction sector is now the secondlargest market for plastics manufacturers after the packaging industry. It uses more than 30 different types of plastics, with PVC predominating, although polystyrene foam,

A wide range of semi-finished plastic products for use in exterior wall structures is available on the market. Depending on the planned load, they can be used to build rigid (resistant to mechanical loads) or flexible (stable under


compression or when subjected to tensile stresses) structures. Plastics can have a variety of physical prop­ erties because a targeted combination of ­various materials or the modification of material properties can produce a great diversity of characteristics. Further processing raw materials in certain ways can produce a wide range of different semi-finished products (Fig. B 7.11, p. 220). Flat, corrugated and multi-wall panels

Plastic panels are usually produced by extrusion, calendering (rolling) and pressing, techniques that can produce flat, corrugated and multi-wall sheets. Polymethyl methacrylate (PMMA) and poly­ carbonate (PC) are usually used to make flat, transparent panels. Their high level of transparency and resistance to weather and impact makes them well suited for use in facades. The common commercially available panel format is 205 ≈ 305 cm. The light transmission level through material 4 mm thick is about 90 %. This material is classified in building material class B 2 in terms of its behaviour in fire. Flat thermoplastic polyester (PET, PETG) ­panels withstand breaking well and are clas­ sified in building material class B 1. Plastics reinforced with glass fibre (GFRP) can be used to produce opaque, free-form panels. Their c ­ orrugated cross section and the resulting greater rigidity mean that corrugated PMMA panels can be made in sizes up to 104.5 ≈ 700 cm and polycarbonate panels up to 126.5 ≈ 400 cm. Corrugated panels up to 300 ≈ 2,000 cm in size can be produced with the addition of GFRP.

Plastics in facades (synthetic plastics)

Elastomers, open cross-linked structure

Thermoplastics, not cross-linked

Thermoset plastics, tightly cross-linked

Polystyrene (PS)

Silicone rubber (SIR)

Formaldehyde resin

Polyethylene (PE)

Polyurethane (PUR)

Unsaturated ­polyester (UP)

Polypropylene (PP)


Epoxy resin (EP)

Polyvinyl chloride (PVC)

Polysulphide rubber

Cross-linked p ­ olyurethane (PUR)

Polymethyl meth­ acrylate (PMMA)

Chloropropene ­rubber

Vinyl ester resin (VE resin)

Fluoroplastics (ETFE, PTFE)

PMMA, crosslinked

Polyamide (PA) Polycarbonate (PC) Saturated ­ polyesters B 7.9

PMMA, PC and GFRP can also be used to make panels with a wide range of different cross ­sections (Fig. B 7.16, p. 221). Their webs and additional diagonal structuring can make them more rigid. PMMA and PC panels are available in lengths up to 700 cm. Integrating cavities into panels gives them a relatively low thermal transmittance coefficient of about 2.5 W/m2K for single-layer panels and up to 1.6 W/m2K for double-wall panels. Using triple or multiwall panels or filling cavities with insulation can further improve this figure. Applying protective coatings or forming multilayer cav­ities makes it possible to modify the panels’ sound insulation and lighting properties to meet specific requirements. GFRP panels are especially suited to this purpose. They are available in a wide range of cross sections and lengths up to 1,500 cm. B 7.6   Dome over Manhattan (US), 1960, Buckminster Fuller B 7.7   Tanzbrunnen, Cologne (DE) 1957, Frei Otto B 7.8   Olivetti Training Centre, Haslemere (GB) 1973, James Stirling B 7.9   Classification of plastics according to degree of crosslinking and resulting material properties [6] B 7.10  Tent roof made from prestressed acrylic glass panels, Olympic Stadium Munich (DE) 1972, Günter Behnisch + Partner, Frei Otto and others

B 7.10



Bavarian Mountain Rescue Service training centre Gaißach near Bad Tölz, DE 2008 Architects: Herzog + Partner, Munich Structural engineers: Sailer Stepan and Partners, Munich Facade technology planning: Hightex, Rimsting º  a+w 12/2008 Baumeister 07/2009 Kunststoffatlas p. 260 –261 Tec 21 05/2009 Umrisse 02/2009 UED 06/2016 • Minimal structural requirements make this simple, transparent protection from the weather sufficient • Facade made of mechanically tensioned ETFE film panels • Panels pretensioned by curved vertical ­compression struts • Self-cleaning effect of the ETFE film keeps maintenance and cleaning costs low

3 8 6




6 7 Top view • Vertical cross section • Horizontal cross section Frame panel Scale 1:20 Cross section detail Scale 1:2.5


b 9

1 Steel profile, 240 mm 2 M12 screw 3 Steel Z-bracket, 3 mm bolted on to form part of the frame 4 Hollow EPDM weather strip, Ø 8 mm 5 ETFE film, 0.20 mm, 0.25 mm or 0.30 mm, depending on structural requirement 6 Hollow steel compression strut, Ø 35 ≈ 8 mm 7 Hollow steel chord, Ø 8 mm 8 Flat steel section, 60/120/5 mm 9 Steel profile section, HEB 240 mm


a 2

2 4


3 9





4 1






6 7


7 A




Plastics 3 2 1

Allianz Arena Munich, DE 2005


Architects: Herzog & de Meuron, Basel º  Archithese 04/2005 Arquitectura viva 91, 2003 Baumeister 06/2005 Hochparterre 08/2005



•6 6,500 m2 two-ply pneumatic foil cushion building shell made of fire-resistant ETFE •T he ETFE structure has a high level of ­daylight transmission and an extremely low dead weight of less than 1.0 kg/m2 • Ventilators create a nominal internal pressure of 450 Pa (facade) and 300 Pa (roof) to stabilise the forms of the diamond-shaped cushions, which can measure up to 4.60 ≈ 17 metres. • Internal pressure can be adjusted to withstand varying wind conditions and snow loads. • LED lights mounted behind the foil cushions can evenly light up the membrane cushions in all the colours in the spectrum. The standard lighting is restricted to red, blue and white.

4 7




9 6


1 LED lights – 24 for each cushion   2 Sun protection roller blind   3 Insulating glazing cladding a post-and-rail facade   4 Prefabricated spun concrete supports, Ø variable   5 Screw connection for spun concrete support   6 Smoothed and painted fibre-cement panel, 2≈ 12.5 mm, mineral wool 100 mm, steel-reinforced concrete edge beam   7 Hollow steel section, 200/300 mm, with rails for lift system   8 Flat steel facade bracket, 2≈ 100/80 mm   9 Compressed air for facade cushion, Ø 100 mm 10 PE compressed air pipe, Ø 50 mm 11 ETFE foil facade cushion, 0.2 mm 12 Ladder for lift system 13 Hollow steel section secondary structure, 120/220 mm 14 Galvanised steel sheeting rainwater gutter, 6 mm 15 Polyolefin profile gutter sealing around the joint, with profiling to absorb movement 16 Flat steel binding piece, 2≈ 250/30 mm 17 Hollow steel section secondary structure, 120/220 mm

2 3 4


1 12


1 17


15 16


7 14 bb

Vertical cross section Scale 1:50 Detail cross section Scale 1:20


Part C  Special topics

Tsinghua University Campus, Beijing (CN) 2006, Mario Cucinella

Interest in facades specifically designed to take on specific functions is growing. This interest is of an experimental nature, on the one hand because building envelopes are being assigned entirely new functional characteristics for which different architectural solutions are currently still being sought. Sufficient experience with such solutions, with their long-term durability, for example, is still lacking. On the other hand, this interest opens up completely new design opportunities whose cogency in terms of the “logic of form” has yet to be proven. Technical correctness, construction methods suitable for specific materials and manufacturing technologies are all fundamentally import­ ant issues in this context. 237


Permeability properties (air, radiation)

Wall surface

Not permeable

Permeable (openings)

Non-variable properties

Element’s manoeuvrability

Variable properties

Immoveable element (rigid)

Manoeuvrable element (manipulators)

Permanently manoeuvrable

Segmenting of element /  size when stowed

One piece

Size when stowed ­unchanged

Temporarily manoeuvrable (fixed)

More than one piece

Size when stowed ­reduced

Size when stowed greatly reduced C 2.2

Just as general technological develop­ ment has altered the performance profile of buildings, the functions of the window and elements in front of openings in build­ ing envelopes have increasingly become more sophisticated and complex. In recent years, the diversity of movement mech­ anisms available for manipulators has grown considerably.

C 2.3

In this context, window manufacturers also seem to be offering more diverse movement mechanisms as alternatives to the turn-and-tilt windows common in Germany, which are also problematic with respect to heating energy consumption criteria. Classification of manipulators

C 2.4

C 2.5


C 2.6 Manoeuvrability

Elements with variable properties can be divided into: •  stationary elements •  moveable elements Stationary elements include thermotropic ­coatings and gasochromic or electrochromic glass. Elements that allow for movement can be characterised by two adjectives [5]: •  temporarily/seasonally manoeuvrable, i.e. can be moved – e.g. storm windows •  permanently manoeuvrable, i.e. made to move The word manipulator refers to facade compo­ nents with variable properties, with permeability to air, light, heat and moisture which can be varied by movement.

The wide range of well-known varieties of manipulators is classified below and may serve as inspiration for new functional, geo­ metric and technical combinations. Three ­factors can be considered when classifying manipulators: •  Permeability properties •  Manoeuvrability of the element •  Segmenting and stowing of the element (changes in volume and /or size)

Segmenting of elements / size when stowed


A manipulator usually consists of one or more parts that can be further subdivided into vari­ ous parts. Together with the type of movement, this results in different states and a range of features of surfaces with modifiable properties. Differences in the size of elements when they are extended or retracted directly influence operation and may determine functional prop­ erties as well as construction and design char­ acteristics.

Surfaces permeable to air, light, heat and moisture are distinguished from those that are impermeable (or almost so). Permeability may or may not be variable. The type and extent of permeability largely determines a surface’s function. If the functional performance profile of a surface is designed to be able to assume different states, the surface’s permeability must be variable.

Changes in the size of manipulators (their size when stowed) are crucial to various ­construction, functional and design aspects of moveable elements in facades. Possible changes in the size of manipulators can be defined as: • unchanged • reduced •  greatly reduced



perpendicular to the plane of the facade



around an axis perpendicular around a to the plane horizontal axis of the element horizontal






unchanged unchanged


















greatly reduced

greatly reduced greatly reduced greatly reduced

greatly reduced greatly reduced

greatly reduced


greatly reduced greatly reduced greatly reduced greatly reduced greatly reduced greatly reduced




The types of movement of manipulators used often combine various movement principles. Figure C 2.7 shows an overview of the wide range of movement options and directions for manipulators [6]. The overview covers types of movement used in practice but does not claim to be exhaustive. If a system consists of a combination of vari­ ous manoeuvrable elements, the movement mechanisms used become fundamentally important. Elements can only move independ­ ently if they do not have a mutually adverse effect on each other [7]. Various aspects can




Types and directions of movement

The fundamental types of movement for elem­ ents in the facade are classified in a list in the chapter on “Edges, openings” (p. 38) based on the movement mechanisms used for windows.




The way components are arranged can directly influence functional factors. Installing a blind to prevent glare in an opening’s upper area can reduce the amount of light reaching deep into an interior. Installing interior solar protec­ tion may result in an unwelcome input of heat energy.

Folding (turning – sliding)

Further distinguishing features

Further aspects of manoeuvrable elements can be differentiated by taking a fourth factor into account, e. g.: •  Position relative to the climatic border: ­outside (at a distance from the opening), ­outside, integrated into the plane of the ­window, inside •  Position relative to the opening: above, in the middle of, below, at the side of, on one or several sides



around a vertical axis


C 2.2  Classification of the word “manipulator” C 2.3  Stone shutters, Torcello (IT) C 2.4  Facade opening with folding shutters and perme­ able arches for refracting light and regulating ­ventilation, Montagnana (IT) C 2.5  Translucent panels, traditional house, Takayama (JP) C 2.6  Combination of several manipulators at Palazzo Pitti, Florence (IT) C 2.7  Classification of common manipulators Figures above the drawings refer to changes in the size of moveable elements when expanded or retracted.



C 2.7


Solar energy

C 3.25

ture, i.e. the electrical separation and circuitry of layers. Solar cells can be specifically used as design elements if, for example, their widths are ­varied or more horizontal dividing lines are added. While reflective layers can expand the range of crystalline cell colours available, dark shades predominate in semiconductorbased thin-film technology. Dye solar cells are available in various shades of yellow, green and red. Photovoltaic modules Around 30 to 60 crystalline cells usually form larger, prefabricated units 0.5 to 1 m2 in size. These PV modules are multilayered, i.e. cells are either inserted between panes of glass, embedded in synthetic resin or encapsulated between ethylene vinyl acetate (EVA) / polyvinyl butyral (PVB) films, set in casting resin or laid between glass and a ­plastic laminate. Depending on requirements, their rear sides can be opaque, translucent (matt glass / light-diffusing films) or transparent (clear glass / transparent films). Thin-film cells can also be applied on soft materials such as membranes. “Sawn”, semi-transparent monocrystalline cells are now available on the market. Thin-film cells can also be printed in a wide variety of ways. Manufacturers offer modules in various standard sizes, although custom-made systems are usually used in facades.

Integrating solar energy systems

In integrating solar collectors and photovoltaic modules, planners must first consider whether they are intended for a cold or a warm facade. Existing approaches have positioned solar energy systems before surfaces that channel water or used them instead of con­ ventional opaque cladding materials or insu­ lating glazing. Additional savings can be made by replacing a structural component with a solar energy system. Whether added onto or integrated flush into the plane of a facade, what is essential for a harmonious design ­solution are the modules’ dimensions, the proportions of the whole element and its internal form, especially its positioning in the plane. Photo­voltaic modules are also used in (balcony) ­parapets and as fixed or moveable solar protection systems. Uniaxial and biaxial tracking systems are one alternative to fixed units. Depending on their orientation and installation situation, their axis of rotation can be horizontal or vertical. Biaxial tracking photovoltaic modules can theoretically use about twice as much solar radiation per year as optimally-oriented fixed systems. The energy yields of biaxial tracking systems are only slightly higher than those of uniaxial systems because of the energy the system uses, so biaxial systems’ more complex mechanism and additional demands due to integration must be considered when planning them. The

C 3.26


cost-benefit ratios of tracking systems must be carefully reviewed because less than 50 % of the radiation available on an annual average is direct radiation. The construction sector is of great relevance for the success of Germany’s transition to renewable energy use. Fewer new buildings are being built so the focus is on existing buildings. Although the potential uses of facades are often limited for various reasons and the energy yields may be less than those from optimally oriented south-facing roofs, ­collectors and PV modules can be integrated into almost every facade, although they are particularly effective used as rear-ventilated cladding material or as fixed components in a glass facade system. Considering the construction aspects of integrating solar power systems, it becomes clear that manufacturers are constantly refining and improving installation conditions – especially fastenings and seals at the sides. New types of frame sections make assembly easier and shorten construction times as well as reducing section heights and visible widths. There are now many ways to flexibly integrate solar energy systems into building ­envelopes and increasing numbers of complete solutions that better combine solar-­ thermal and photovoltaic systems within a type of construction technique with each other and with other elements in the envelope. A wide range of tried and tested systems for common types of facades is available on the market [12]. Collectors and PV modules must be integrated into the building’s technical services and, depending on the type of use, cable ­routing and additional technical apparatus may also be required. The relatively slender structures and flexible, thin electricity cables of photovoltaic systems make them especially suitable for integration into facades. Water collectors, in contrast, have pipes with a much larger diameter that must not leak and the system must usually be filled with antifreeze agent.

Solar energy

C 3.27

In terms of formal aesthetic criteria, there is a wide range of design options for integrating solar power systems into building envelopes. The range of colours of absorber surfaces and formal diversity of profiles influence the look of systems, as do elements connecting sides and facade surfaces. Architects will often hear that the wide range of colours available is a special bonus of photovoltaic systems (Fig. C 3.27). Adding colours and forms to a building envelope is an especially sensitive design task that impacts a building’s appearance and requires careful and thorough consideration. In the context of colour, there is ­currently often a demand for very consistent surface designs that use crystalline PV modules. Colouring conductors (bus bars) and rear-side contacts can make cells fit in and look like homogeneous surfaces so that films or glass coatings of the same colour connected with modules are almost no longer identifiable as such (Figs. C 3.25 and C 3.26). Architecturally integrating solar power systems into a building envelope is a momentous undertaking. It involves incorporating systems into roofs and walls in a structurally and functionally cogent manner and in an aesthetically consistent form that takes the building’s specific characteristics into account and combines them to form a single architectural entity comprising the building’s features and (compositional) lines of solar energy systems. The quality of this integration is influenced by the construction, material, colour, surface, size, proportion and arrangement of components and the structural system as a whole must always be borne in mind [13].

Notes:   [1]  PV modules and tube collectors were used for the first time in 1982 in a Munich housing estate ­designed by Thomas Herzog and Bernhard ­Schilling, working with the Fraunhofer Institute for Solar Energy Systems in Freiburg.   [2]  Krippner, Roland: Die Gebäudehülle als Wärmeerzeuger und Stromgenerator. In: Schittich, Christian (ed.): Gebäudehüllen. Konzepte, Schichten, Mate­ rial. 2nd ed., Munich 2006, p. 48   [3]  Henning, Hans-Martin; Palzer, Andreas: 100 % ­Erneuerbare Energien für Strom und Wärme in Deutschland. Im Rahmen von Eigenforschung ­erstellte Studie. Freiburg 2012, p. 4f.   [4]  Koblin, Wolfram et al.: Handbuch Passive Nutzung der Sonnenenergie. Schriftenreihe des BMI für Raumordnung, Bauwesen und Städtebau 04, Bau- und Wohnforschung. Bonn 1984, p. 93 – 99   [5]  Herzog, Thomas et al.: Gebäudehüllen aus Glas und Holz. Maßnahmen zur energiebewussten Erweite­ rung von Wohnhäusern. Lausanne 1986, p. 8, 15   [6]  As for Note 4, p. 118, 135ff.   [7]  Goetzberger, Adolf; Wittwer, Volker: Sonnenenergie. Thermische Nutzung. Stuttgart 1993, p. 146f.   [8]  Nachtigall, Werner; Pohl, Göran: Bau-Bionik. Natur – Analogien – Technik. 2nd edition, Berlin / Heidelberg 2013, p. 41– 46   [9]  Also sometimes referred to as “transparent” thermal insulation. The adjective “transparent” is confusing here because these materials are permeable to ­radiation but not necessarily transparent. A clear distinction must be made for construction purposes between “diaphanous / translucent” and “clear /  transparent”, so it is referred to as “translucent” thermal insulation. [10]  Herzog, Thomas: Transluzente Bauteile. Anmer­ kungen zu ihrer Wirkung. In: Almanach 90/92. FB Architektur der TH Darmstadt. Darmstadt 1992, p. 94ff. [11]  Krippner, Roland: Architektonische Aspekte solarer Energietechnik. In: 9th Symposium on Thermal Solar Energy. Conference transcript. Regensburg 1999, p. 237 [12]  Krippner, Roland (ed.): Gebäudeintegrierte ­Solartechnik. Detail green books. Munich 2016 [13]  Krippner, Roland: Solartechnik in Gebäudehüllen. In: Detail Green, 01/2012, p. 53 – 57

C 3.25  Aktiv-Stadthaus apartment building in Frankfurt /  Main (DE) 2015, HHS Planer und Architekten C 3.26  Children’s daycare centre, Marburg / Lahn (DE) 2014, opus Architekten C 3.27  Paul-Horn-Arena, Tübingen (DE) 2004, Allman Sattler Wappner


Solar energy

Oskar von Miller Forum Munich, DE 2009 Architects: Herzog + Partner, Munich Facade designed in cooperation with FKN Fassaden, Neuenstein º  Baumeister 06/2010 UED 06/2016 World architecture 245, 2010 Herzog, Thomas (ed.): Oskar von Miller Forum. Munich 2010 aa

• International meeting centre for the support of trainee construction engineers with a ­multifunctional hall, library and bistro on the ground floor, offices and apartments on the upper storeys • 400 m2 of vacuum tube collectors provide ­stationary shade for the top floor and supply 20 % of the heating energy required in the building and 16 % of cooling energy requirements • Slender photovoltaic louvres in front of glazed entry area on the south-east facade provide additional solar protection • Silver-grey glossy polycrystalline cells fixed along longitudinal sides

Cross section  Scale  1:750 Vertical cross section  Scale  1:5   1 Dual-glass photovoltaic module 12 mm   2 Aluminium U-profile frame 40 ≈ 3 mm   3 Frame attachment, flat aluminium section 60 ≈ 5 mm, cable routing in OL 90 cover   4 Square hollow aluminium spacer 20 ≈ 2 mm   5 System attachment to posts, triple-screwed   6 Double insulating glazing 39 mm   7 Cavity for cable routing 80 ≈ 18 mm   8 Post attachments, fixed bearing   9 Post attachments, loose bearing 10 Floor structure: Natural stone in an adhesive mortar bed 30 mm Screed 90 mm Reinforced concrete ceiling 150 mm

3 2


5 4 10

6 7 8 9



Solar energy

SwissTech Convention Center Lausanne, CH 2012 Architects: Richter Dahl Rocha & Associés, Lausanne º  DBZ 04/2015 Fassade, Facade 03/2014 Haustech 06/2014 Tec 21 49 – 50, 2013


• Main building for an extension to the École polytechnique fédérale de Lausanne (EPFL) campus • A convention centre designed to accommodate 3,000 people, central foyer with a glass facade covers the full height of the building • Angled, full-storey, dual-glass modules in ­narrow strips cover 300 m2 of the west facade; angles range from 7.5° to 45° in increments of 7.5° •D ye-sensitised solar cell modules in various shades of yellow, green and red • First use of Grätzel cells on this scale





5 3




5 a








5 aa

Cross section  Scale  1:1,000 Vertical cross section, west facade  Scale  1:20 Horizontal cross section through a facade detail  Scale 1:5 1 Steel facade support 2 Double glazing 14 mm + space between the panes 17 mm + 8 mm, fixed along sides in glazing bars 3 Anodised aluminium cover 4 Hollow square steel section 50/50/5 mm 5 Dual glass solar panels in anodised aluminium frames Four modules (2,100 ≈ 410 mm) in each panel at 350 ≈ 500 mm, each with a 13 ≈ 2 cm-wide strip of Grätzel cells



Annual primary energy requirements for heating [kWh/(m2·a)]

Refurbishing existing facades

450 400 Minimum regulatory requirements (WSchV / EnEv) depending on building geometry

350 300 250 200 150

Building practice

Solar-powered buildings


Low-energy buildings


Passive / “3-litre” buildings


Zero heating energy buildings Plus-energy buildings

-50 1970





construction can usually improve insulation and can even allow a building to meet the current demands made on new buildings. In this context, studies have shown that EU Directive 2012/27/EU, which aims to establish an almost entirely CO2-neutral building stock, can be implemented with an assumed annual renovation rate of 2 % [2]. Here the focus is on facades because, compared with other areas of the building envelope such as the roof, cellar ceiling and foundation plate, they represent by far the largest area in contact with the outside air or ground (with the exception of large halls). This is especially the case with multistorey buildings, which have a much higher proportion of facade area compared with roof area than one or two-storey buildings. Measurements of average multistorey 1950s apartment buildings have shown that the rate of transmission heat loss through their opaque exterior walls is about 16 % and 12 % through windows. To this are added ventilation heat losses of around 20 %, so with a total of 48 % they lose almost half of all their heat through exterior walls or facades. The remaining heat is lost due to transmission heat losses through the roof (17 %) and cellar ceiling (7 %) and power lost by heating systems (28 %). By comparison, a typical 1960s apartment building loses far more heat through its facade – around 63 %. Here heat losses are generally broken down as follows: windows 19 %, walls 22 %, ventilation 22 %, roof 4%, ­cellar ceiling 4 % and unused heating energy 29 % [3]. These heat loss rates make it clear that refurbishing measures to improve energy use must include facades. For a holistic solution that makes use of all energy-saving potential, the insulation of roofs and cellars and optimisation of heating systems must be equally considered and coordinated in measures. Depending on the building’s age, various measures may focus on different areas, although the facade always plays a central role ensuring adequate thermal insulation [4]. 330







Influencing factors and measures Measures to improve a facade’s energy balance can be carried out in a wide range of ­different ways. Factors that may influence the choice of renovation concept include: •  Building’s actual condition in terms of measured energy consumption •  Actual state of a structure’s existing substance and energy consumption and the structural and functional quality of the facade and exterior walls •  Actual condition of current building technologies •  Architectural quality of existing structural substance •  Legally-binding historic building and area conservation regulations and possibly copyright laws •  Any planned changes in usage that may impact future comfort requirements •  Future energy supply options for the building to be refurbished •  Relation between investment costs and any future reductions in operating costs The analysis and prioritisation of these factors greatly influences the development of any overall concept for refurbishing a facade in order to improve its energy use. A refurbishing strategy for a historic building listed as protected will usually be very different from the refurbishing of an average building that is not subject to such protection to modify its energy consumption. When a building is converted (e.g. from commercial to residential use), the changed comfort requirements will mean that refurbishing its facade will involve measures different from those that would be required if its use were to remain the same. What all these measures have in common is the aim of improving the facade’s thermal performance. This can be done by partly or completely replacing or supplementing indi­ vidual structural elements, windows, glass facades, glazing and/or frames. The thermal performance of facades and exterior walls can also be optimised by adding extra layers (e.g. of insulation) or shells (e.g. glass skins

C 5.2

or opaque facing shells of rear-ventilated facade structures) [5]. Taking these aspects into account, a distinction can be made between the following possibilities: •  Interior insulation attached at a distance to a preexisting facade or exterior wall (housein-a-house concept, Fig. C 5.3) •  Interior insulation attached without any gap to a preexisting facade or exterior wall (Figs. C 5.4, C 5.11, p. 335) •  Partial replacement, supplementation or complete replacement of preexisting facade or window (Figs. C 5.12, C 5.13 and C 5.14, p. 335) •  Exterior insulation attached without any gap to a preexisting facade or exterior wall (Figs. C 5.15, C 5.16, p. 335) •  Exterior facing shell attached at a distance to a preexisting facade or exterior wall (Fig. C 5.17, p. 335) Various options for refurbishing and improving energy use are presented and explained below. It should be noted that in practice these possibilities are often combined to achieve an optimum result, depending on the specific conditions and requirements. Interior insulation Refurbishing of the inside of a facade or external walls to improve their energy use is usually carried out if insulation cannot be added to the outside of existing exterior walls because they are part of an especially elaborate plaster, halftimbered or clinker facade, or for design and / or historic building conservation reasons [6]. The advantages of this refurbishing method are that it maintains the building’s external appearance and does not require official approval. It is also usually less expensive to add insulating layers (e.g. mineral foam or calcium silicate boards) to an interior than to install thermal insulation composite systems or rear-ventilated systems on the outside. A loss of floor space is however one disadvantage of this approach for a structure’s physical

Refurbishing existing facades

C 5.3

properties. Interior thermal insulation also means that an exterior wall’s thermal mass can no longer compensate for the interior climate. Interior thermal insulation also means that during cold times of year the exterior wall is no longer warmed, so it cools markedly and temperatures may fall below freezing much more often. Thermal bridge effects, especially around connecting walls and ceilings, also have a major effect on temperatures. Steel Å-beams and timber beams penetrate the insulating layer at support points and project into the cold exterior wall. Balconies are directly connected to the outside, so are at risk from condensation. Water, drainage and heating pipes laid in the exterior wall are also at greater risk of freezing due to more extreme cooling. To prevent damp from damaging an exterior wall insulated on the inside, a vapour barrier should be mounted on the inside to prevent condensation from accumulating, although a vapour barrier may be dispensed with if vapourproof insulating material is used. Another alternative is the use of calcium silicate boards because they are porous and can absorb moisture and release it in into dry interior air. Their high pH levels also prevent the growth of mould. Structural surveys to resolve such issues must always be carried out before such measures are initiated to prevent any subsequent damage [7].

Replacing windows and facades The relatively high heat transmission coefficients of glazing installed in buildings decades ago means that the thermal performance of their windows and glass facades must be carefully considered. Solar radiation can easily pass through windows or glass facades into a building and cause it to overheat in summer. In hot climates in particular, solar radiation can intensely heat up glass and frame surfaces. This heat can be transferred to the interior by means of heat transfer, radiation and convection, creating an uncomfortable indoor climate and usually increasing the energy consumption required for cooling. Heat losses through windows and glass facades can cool down interiors during cold times of year. The interior surfaces of windows and glass facades can cause cold downdraughts and draughts near glazing, and radiative cooling

can make the interior climate uncomfortable. If there are also leaks in and around a window frame or glass facade, draughts and ventilation heat losses can result in excessive energy consumption, further undermining users’ wellbeing. A range of overlapping factors (glazing and /or frames with inadequate U-values, leaky and defective window frames) means that windows and facades are often completely replaced with thermally separate window or facade sections and multilayer insulating glazing (possibly with an inert gas filling) to greatly improve the U-values of windows or facades. While a single-glazed timber window frame of the kind common until well into the 1950s may have a UW-value of 5 W/m2K, a thermally separate window frame combined with triple insulating glazing can currently achieve a ­ W-value of 0.9 W/m2K [9]. U

As well as insulation systems directly attached to the inside of an external wall, there are other refurbishing concepts that attach an additional insulating layer at some distance from the ex­­ terior wall. This additional zone of intermediate temperature can serve as a thermal buffer or weather-protected useable space [8].

C 5.2  Trends in energy-saving construction in Germany since the passing of the 1st Thermal Insulation Regulation in 1977 C 5.3  Two-ply film membrane interior insulation forms a ventilated zone of intermediate temperature, ­Siemens factory hall, Munich (DE) 1997, Thomas Herzog with José-Luis Moro C 5.4  Interior insulation, “Birg mich, Cilli!”, Viechtach (DE) 2008, Peter Haimerl Architektur

C 5.4


Green facades

the environmental movement beginning in the 1970s came a renewed focus on the import­ ance of plants in buildings and life. The green roofs of suburban “eco-housing” estates in particular became spaces for planting designs. Facades have increasingly been used for this purpose since around 1980. The structural significance of plantings

C 6.2

C 6.3

A functional use of vegetation can have nat­ ural, organic effects that positively influence the microclimate around a facade. Plants can, for example, be used as natural sunshades in front of transparent openings. Depending on their type and position, growth habit and degree of leaf coverage, shade plantings can help regulate the temperatures of layers of air near facades. The botanical features of the type of plants used play a vital role in the effects that can be achieved [6]. Plantings on opaque walls can reduce their surface temperatures and positively affect the microclimate. Some types, such as evergreen climbing plants (e.g. ivy or honeysuckle) can form cushions of air with their dense foliage across large areas, reducing the cooling of wall surfaces in winter and so functioning as extra insulation. In contrast to conventional insulation materials, the effects that can be achieved vary with different plants and nat­ ural seasonal changes and depend on the plants’ development and, in the case of wallmounted systems, on soil moisture. Studies have shown that even well-insulated walls can benefit from the additional insulating effects of plants [7]. Decreasing facade surface temperatures can also reduce the need to use compact, decentralised ventilation units (see the chapter on “Integrated facades”, p. 322ff.) while ensuring that growing demands for fresh-air quality are met with greater energy efficiency. Classifications

C 6.4

Green facades can be classified into soilbased types using climbing plants and wallmounted types with special planting systems (Fig. C 6.6). Soil-based green facades

C 6.5


Plants used in soil-based green facades can generally be classified based on their climbing behaviour as self-clinging climbing and climbing plants requiring support: •  Self-clinging climbing plants can cling directly to a wall surface and spread out in a fan shape. Direct planting with ivy or Virginia creeper is inexpensive and requires relatively little maintenance but not every exterior wall is suitable for this purpose. To avoid damage to buildings, such plants should only be planted against solid walls (masonry, concrete) (Figs. C 6.2 and C 6.4).

•  Climbing plants requiring support need a trellis or similar and based on their climbing behaviours can be classified into twining climbers (e.g. wisteria, honeysuckle) and creepers (e.g. grapevines, clematis). These plants grow autonomously upwards along trellises / espaliers (Fig. C 6.3) – particularly mesh or grid structures, but linear structures with rods, tubes or cables can also be used. Their spread is largely limited by the trellis. Climbing plants need regular pruning. It must be ensured that the plants are accessible and the cost and effort involved in maintaining them should be taken into consideration in planning appropriate systems. The speed of growth and climbing behaviour of plants as well as the building’s height must be considered when designing soil-based green facades. Such plantings can last for 5 to 20 years (self-clinging climbing plants) or 3 to 12 years (climbing plants). Around 150 types and species of climbing plants are suitable for green facades in Germany. Such plantings use a technique that has been developed and refined for centuries and can be applied with relatively little additional effort to a wide range of exterior wall surfaces [8]. Construction technology Soil-based green facades need a certain amount of space in front of the plinth of the exterior wall where plants can be planted and develop roots. Planting substrata must be carefully positioned to ensure that water can run off and roots can grow away from the building. The construction and anchoring of trellises is of vital importance. Fasteners (hanger bolts, bolt and wall anchors, spacers) anchor planar or linear structures in the load-bearing layer of the external wall. Possible thermal bridges must be considered and mounting and fastening components can be complex and costly if layers of insulation are very thick. Added structural loads must be considered if plants such as wisteria are used in multistorey plantings, although facade plantings usually take many years to grow into huge, heavy masses of vegetation. Structures must be able to easily bear such loads from the outset. Sufficient distance from sunshading systems and openings is important because plants can quickly grow into cavities and /or moving parts and block them (Fig. C 6.1, p. 336). Structures added to the fronts of facades (Fig. C 6.10, p. 341) such as balconies and access and maintenance walkways are also suitable for (subsequent) greening. C 6.2  Castello Sforzesco, Milan, (IT) 1450ff. C 6.3  Goethe's garden house, Weimar (DE) 16th / 18th century C 6.4  Villa Bonnier, Stockholm (SE) 1927 C 6.5  Magistratsabteilung 48 office building, Vienna (AT) 2010 C 6.6  Construction and vegetation parameters of decisions on green facades [9]

Green facades

Soil-based greening

Facade greening

Planar growth directly on the facade

Climbing plants that can be t­ rained (depending on climbing strategy)

Plants in horizontal plantings, plant containers on support structures

Self-climbing plants: Root ­climbers, holdfast climbers

Climbing and twining plants, shrubs on espaliers

Perennials (e.g. grasses, ferns, bulbs and tubers to some ­extent), small shrubs, climbing and twining plants, spreading climbing plants to some extent

Perennials (e.g. grasses, ferns), small shrubs, mosses; root climbers to some extent, spreading climbing plants

Perennials (e.g. grasses, ferns), small shrubs, mosses; root climbers to some extent, spreading climbing plants

• No trellis necessary

• Trellises / espaliers required (rods, tubes, cables, grids, nets)

• Substrata in containers (individual and linear containers)

•S ubstrata in elements consisting of baskets /gabions, mats, tubs • Substrate-bearing trough ­system irectly planted artificial or nat­ •D ural stone panels with rough surfaces conducive to plant growth

• Textile systems •T extile substrata systems •S heet metal systems with ­openings for plantings (textile or substrate carrier) •D irect greening on nutrient-­ bearing wall shells

Design criteria Surface effect in 5 –20 years*

Surface effect in 3 –12 years*

modular systems        planar structures

Surface effect with pre-culture: short-term

Surface effect with pre-culture: immediate

Scope for creative design: medium

Scope for creative design: low to medium

Plants in vertical plantings – “vertical gardens”

Scope for creative design: large

Structural and technical requirements

Rooting in soil /connected to topsoil and soil moisture

Rooting in substratum system / no connection with soil and soil moisture required, no contact with subsoil

Water supply depends on location, as required

Water and nutrient supply system required Building authority approval may be relevant, certification of structural soundness necessary, load-bearing structural elements must be protected from corrosion or made of a rustproof material Facade must be protected from moisture and root penetration

Suitable for following walls • Solid walls (ensure joints are closed and ­exterior skin is intact Check that surface is suitable for the plant physiology*)

• Solid walls • Timber structures, completely covered or filled in (limited*) • Metal structures, completely ­covered or filled in (limited*) • Facing shells (limited*) • Curtain wall facade (limited*) • Composite thermal insulation systems • Air collector facades

• Solid walls • Timber structures, completely covered or filled in (limited*) • Metal structures, completely covered or filled in (limited*) • Facing shells (limited*) • Curtain wall facade (limited*) • Composite thermal insulation systems • Air collector facades

• Solid walls •T imber structures, completely covered or filled in (limited*) etal structures, completely •M covered or filled in (limited*) • Facing shells (limited*) • Curtain wall facade (instead*) omposite thermal insulation •C systems (limited*)

• Solid walls •T imber structures, completely covered or filled in (limited*) •M etal structures, completely ­covered or filled in (limited*) • Facing shells (limited*) • Curtain wall facade (instead*) •C omposite thermal insulation systems

Economic criteria Investment costs: low

Investment costs: low to high

Investment costs: medium to high

Investment costs: high

Potential savings in facade design depending on plant growth

Immediate potential savings in facade design

Maintenance requirements: medium, increasing*

Ecological potential

Care and maintenance cost and effort: low*

Maintenance requirements: medium to high / horticultural*


Care and maintenance cost and effort: medium to high*

Care and maintenance cost and effort: high

Shading – relevant over the course of the year deciduous plants

Possible species variety (flora / fauna) at the site: low to high* Microclimatic relevance: medium to long-term*

Microclimatic relevance: medium-term*

Possible species variety (flora / fauna) at the site: medium*

Possible species variety (flora / fauna) at the site: great*

Immediate microclimatic relevance with pre-culture*

* Figures supplied by the FBB (green buildings industry association), Projektgruppe Fassadenbegrünung (facade greening project group), FLL (Research society for landscape development and landscaping), Regelwerk-Ausschuss Fassadenbegrünung Grundlage (facade greening regulations committee – sources): diagrams and content 1), additions by the author, ©Nicole Pfoser, 07/2011 1)  FLL, 2000; Kaltenbach, 2008; Pfoser, 2009, 2010 a, 2010 b, 2011 a, 2011 b, 2011 c C 6.6



Thomas Herzog

Roland Krippner

Werner Lang

1941 Born in Munich 1960 –1965 Studied architecture at the Technical Uni­ versity of Munich and in parallel completed training in metalworking and ceramics trades 1965 –1969 Employed in the architects’ firm of Prof. Peter C. von Seidlein, Munich 1969 –1973 Research assistant to the Chair of Building Construction and Design at the University of Stuttgart 1971–1972 Studied at Deutsche Akademie Villa Massimo in Rome 1972 Doctorate from Rome’s La Sapienza University since 1971 he has worked with partners at his own firm in Stuttgart / Munich 1973 – 2006 university professor   - at University of Kassel, for Design and Product Development   - at the Technical University of Darmstadt for Design and Building Technologies   - at the Technical University of Munich (TUM), Institute for “Design and Building Technology”, full professor for “Building Technology” and Dean of the Faculty of Architecture since 2007 “Emeritus of Excellence” at the Technical ­University of Munich Visiting professor in Lausanne, Copenhagen, Philadelphia and Beijing

1960 Born in Frankfurt / Main 1976 –1980 Trained as a mechanic 1982 –1987/1989 –1993 Studied architecture at the ­University of Kassel 1993 Awarded his degree (II) and an award from the Deutscher Stahlbau-Verband (German Steel Construction Federation), 3rd prize 1996 1988 –1989 Civilian service year at Landesamt für Denkmalpflege Hessen (Hessen State Office for Historic Buildings Conservation) in Marburg Since 1989 publishing work 1993 –1995 Worked at the Büro für Architektur und Stadtplanung (BAS), Kassel since 1995 Freelance architect (R&D projects), author, lecturer 1995 – 2006 Research assistant / assistant to the Chair for Building Technologies, Prof. Dr. (Rome University) Thomas Herzog, Faculty of Architecture, TUM 2004 Doctorate (Dr.-Ing.) at TUM on “Untersuchungen zu Einsatzmöglichkeiten von Holzleichtbeton im Bereich von Gebäudefassaden” (Investigations into applications for lightweight wood chip concrete in building facades) (Deutscher Holzbaupreis 2005; shortlisted in the “In­­ novative building products” category) 2005 – 2006 Lectureship at Salzburg University of Applied Sciences 2006 – 2007 Research assistant to the Chair for Industrial Design, Prof. Dipl.-Des. Fritz Frenkler, TUM 2006 – 2007 Deputy professorship for Environmentally Conscious Design and Construction at the University of Kassel 2008 Lectureship at Munich University of Applied ­Sciences Since 2008 Professor for Construction and Technology at Technische Hochschule Nürnberg Georg Simon Ohm

1961 Born in Marktoberdorf 1982 –1988 Studied architecture at Technical University of Munich (TUM) 1985 / 86 Further studies at the Architectural Association, London 1988 Awarded his degree (recipient of the Hans Döllgast Prize) from TUM 1988 –1990 Fulbright Scholarship to study at the University of California, Los Angeles (UCLA) 1990 Master of Architecture II (UCLA), Award for Best Thesis from the UCLA School of Architecture and Urban Planning 1990 –1994 Employed at Kurt Ackermann + Partner firm of architects, Munich Since 1994 publishing work 1994 – 2001 Research assistant to the Chair for Building Technologies, Prof. Dr. (Univ. Rom) Thomas Herzog, Faculty of Architecture, TUM 2000 Awarded his doctorate (Dr.-Ing.) by TUM and recipient of the doctoral prize from Bund der Freunde der TUM (the Friends of TUM) 2001– 2006 Employed at Werner Lang firm of architects, Munich 2001– 2007 Lecturer on “Special facade construction ­topics” and “Building materials” at the Faculty of Architecture, TUM 2006 Co-founder of Lang Hugger Rampp GmbH Architekten architects’ firm, Munich 2008 – 2010 Associate Professor for Sustainable Planning and Construction at the University of Texas at Austin School of Architecture (UTSoA) 2009 – 2010 Director of the Center for Sustainable Development at UTSoA Since 2010 University professor for Energy-efficient and Sustainable Design and Building at TUM; Head of the Centre for Sustainable Building at TUM; spokesman for the Centre for Urban Ecology and ­Climate Adaptation (ZSK) at TUM Director of the Oskar von Miller Forum, Munich

Member of Akademie der Künste (Academy of the Arts, Berlin), Académie d’Architecture (Paris), the Bavarian Academy of Fine Arts (Munich), the St Petersburg State Academic Institute of Fine Arts, Sculpture and Architecture, Fraunhofer Gesellschaft (Munich) and the Inter­ national Academy of Architecture (Sofia). Awards (Selection): 1981 Mies-van-der-Rohe Prize 1993 Gold medal /Grand prize from the Bund Deutscher Architekten (Association of German Architects) 1994 Balthasar-Neumann Prize 1996 Auguste-Perret Prize from the International Union of Architects (UIA) for applied technology in architecture 1998 Den grønne Nål from the Association of Danish Architects 1998 Leo-von-Klenze Medal 1998 “Grande médaille d’or d’architecture” from the French Academy of Architecture 1999 Fritz-Schumacher Architecture Prize 2005 Heinz-Maier-Leibnitz Medal 2006 European Award for Architecture and Technology 2007 Honorary doctorate from Ferrara University in Italy 2009 Global Award for Sustainable Architecture He has exhibited his work in numerous international group and solo exhibitions and published books and monographs in many languages. www.thomasherzogarchitekten.de


Awards: 2008 International Building Skin Tech Award, in collabor­ ation with T. Herzog and K. Stepan, ZAE Bavaria 2000 Bavarian Energy Prize from the Bavarian Ministry of Economic Affairs and Media, Energy and Technology 2000 Holzkreativ Prize from Friends of the Earth, Germany (Bund für Umwelt und Naturschutz), honourable mention in the timber construction category www.langhuggerrampp.de www.oskarvonmillerforum.de

Image credits

The authors and publisher would like to sincerely thank everyone who contributed to this book’s production by providing images, granting permission to reproduce their work, and supplying other information. All the diagrams in this book were created especially for it. The authors and their staff created those graphics and tables for which no other source is credited. Photos for which no photographer is credited are architectural or work photos or come from the archive of DETAIL magazine. Despite intensive efforts, we have been unable to identify the copyright holders of some images, but their entitlement to claim copyright remains unaffected. In these cases, we would ask you to contact us. Figures refer to ­illustration numbers. Shell, wall, facade   1 Stefan Cremers, Karlsruhe   2 Verena Herzog-Loibl, Munich   3 Jan Cremers, Munich   4 Christian Schittich, Munich   5 Pepi Merisio, Bergamo, from Merisio, Pepi; ­Barzanti, Roberto: Italy. Zurich 1975, p. 216   6 Achim Bednorz, Cologne   7 Pepi Merisio, Bergamo, from Merisio, Pepi; ­Barzanti, Roberto: Italy. Zurich 1975, p. 218   9 –11 Verena Herzog-Loibl, Munich 13 Pictor International 14 Thomas, Herzog, Munich 15 Thomas Robbin, Herten 16 Jan-Oliver Kunze / LIN, Paris / Berlin 17 doublespace photography, Toronto 19 Verena Herzog-Loibl, Munich 20 Ogawa, Shigeo / Shinkenchiku-sha, Tokyo

Part A

p. 16 From Lampugnani, Vittorio Magnago, Architektur unseres Jahrhunderts in Zeichnungen. Utopie und Realität. Stuttgart 1982 External and internal conditions A 1.3 – 5 Federal Office for Building and Regional ­Planning (Bundesministerium für Raum­ ordnung, Bauwesen und Städtebau) (pub.): Handbuch Passive Nutzung der Sonnenenergie. Heft 04.097. 1984, p. 78 /52 A 1.6 DIN 4710 A 1.9 Kunzel und Gertis, 1969 A 1.10 Deutscher Wetterdienst, Klima- und Umwelt­ beratung. Hamburg A 1.11 Federal Office for Building and Regional Planning Bundesministerium für Raumordnung, ­Bauwesen und Städtebau (pub.): Handbuch Passive Nutzung der Sonnenenergie. Heft 04.097. 1984, p. 14 A 1.13 –15  Kind-Barkauskas, Friedbert et al.: Beton Atlas. Munich /Düsseldorf 2001, p. 79 A 1.20 From Pültz, Gunter, Bauklimatischer Entwurf für moderne Glasarchitektur. Passive Maßnahmen der Energieeinsparung. Berlin 2002, p. 89 A 1.23 European Wind Atlas Surfaces – structural principles A 2.1.1 Peter Bonfig, Munich A 2.1.7 Herzog, Thomas; Nikolic Vladimir: Petrocarbona Außenwandsystem. Bexbach 1972 Edges, openings A 2.2.1 Dieter Leistner /ARTUR IMAGES A 2.2.3 Schittich, Christian (pub.): Solares Bauen. ­Munich / Basel 2003, p. 63 A 2.2.6 Zürcher, Christoph; Frank, Thomas: Bauphysik. Bd. 2 Bau und Energie – Leitfaden für Planung und Praxis. Zurich / Stuttgart 1998, p. 80 A 2.2.9 –10  Fassade /Façade 03/2002, p. 24f. db 09/2003, p. 87f.

Modular coordination A 2.3.1 Andrew Neuhart, El Segundo A 2.3.2 Yoshida, Tetsuro: Das japanische Wohnhaus. Berlin 1954, p. 69 A 2.3.3 Durand, Jean-Nicolas-Louis: Précis des leçons II. Paris 1819 A 2.3.4 Kunstverein Solothurn (pub.): Fritz Haller. Bauen und Forschen. Solothurn 1988, p. 3.1.4 A 2.3.7 Bussat, Pierre: Die Modulordung im Hochbau. Stuttgart 1963, p. 31 A 2.3.9 DIN 18 000. 1984 A 2.3.13 Girsberger, Hans (pub.): ac panel. Asbest zement-Verbundplatten und Elemente für Außenwände. Zurich 1967, p. 46 – 49 ­ hysics and planning Aspects of building p advice A 3.1 Frank Kaltenbach, Munich A 3.2 Cremers, Jan (pub.): Atlas Gebäudeöffnungen. Munich 2015, p. 50 A 3.3 Detail 9/2002, p. 1,070 A 3.4 – 5 Pfeifer, Günter et al., Mauerwerk Atlas. Munich / Basel 2001, p. 186, p. 190 A 3.6 Bollinger, Klaus et al.: Atlas Moderner Stahlbau. Munich 2011, p. 119 A 3.7 Herzog, Thomas et al.: Holzbau Atlas. Munich 2003, p. 71 A 3.8 – 9 Schüco International A 3.10 –11  Hart, Franz et al.: Stahlbau Atlas. Brussels, 1982, p. 338f. A 3.12 Schüco International

Part B

p. 62 Wimmershoff, Heiner; Aachen Natural stone B 1.1 Eloi Bonjoch, Barcelona B 1.2 – 3 Verena Herzog-Loibl, Munich B 1.4 Christian Schittich, Munich B 1.5 Verena Herzog-Loibl, Munich B 1.6 Luciano Chiappini, Ferrara und seine Kunst­ denkmäler. Bologna 1979, p. 39 B 1.7 Hugues, Theodor et al.: Naturwerkstein. Munich 2002, p. 72 B 1.8 Pepi Merisio, Bergamo, from Merisio, Pepi; Barzanti, Roberto: Italy. Zurich 1975, p. 247 B 1.9 Eloi Bonjoch, Barcelona B 1.10 Müller, Friedrich, Gesteinskunde. Ulm 1994, p. 196 –197 B 1.11 Hugues, Theodor et al.: Naturwerkstein. Munich 2002, p. 72 B 1.12 Thomas A. Heinz, Illinois B 1.13 Zooey Braun/ ARTUR IMAGES B 1.14 –16  Sandsteinmuseum Havixbeck B 1.17 Stein, Alfred, Fassaden aus Natur- und Betonwerkstein. Munich 2000, p. 58 B 1.18 – 22  Detail 06/1999, p. 1026 B 1.23 Verena Herzog-Loibl, Munich B 1.24 Müller, Friedrich: Gesteinskunde. Ulm 1994, p. 171 B 1.25 – 26  Detail 06/1999, p. 1032 B 1.27– 30  Christian Gahl, Berlin B 1.31– 37  From Hugues, Theodor et al.: Naturwerkstein. Munich 2002, p. 51ff. B 1.38 Gundelsheimeer Marmorwerk, Treuchtlingen B 1.39 Müller, Friedrich: Gesteinskunde. Ulm 1994, p. 196 –197 B 1.40 – 49  Hugues, Theodor et al.: Naturwerkstein. Munich 2002, p. 74ff. p. 74 Doris Fanconi, Zurich p. 75 www.kunstverlag-peda.de p. 76 Philippe Ruault, Nantes p. 78 Thomas Lenzen, Munich p. 79 Stefan Müller, Berlin p. 80 © Rupert Steiner, Vienna p. 81 Frank Kaltenbach, Munich p. 82, 83  Roland Halbe, Stuttgart p. 84 André Mühling, Munich p. 85 top:  Victor S. Brigola, Stuttgart p. 85 bottom:  André Mühling, Munich

Clay B 2.2 Ulrike Enders, Hanover B 2.3 Pfeifer, Günter et al.: Mauerwerk Atlas. Munich / Basel 2001, p. 57 B 2.5 Hirmer Fotoarchiv; Munich B 2.6 Budeit, Hans Joachim; Kuenheim, Haug von, Backstein, die schönsten Ziegelbauten ­zwischen Elbe und Oder. Munich 2001, p. 33 B 2.7 Manfred Klinkott, Karlsruhe B 2.8 Chabat, Pierre (pub.): Victorian Brick and ­Terra-Cotta Architecture. New York 1989, p. 18 B 2.9 Halfen GmbH & Co. KG B 2.10 Ulrike Enders, Hanover B 2.11 Halfen GmbH & Co. KG Pfeifer, Günter et al., Mauerwerk Atlas. Munich / Basel 2001, p. 125 B 2.12 Kunstbibliothek Berlin B 2.13 Fischer-Daber, from l’Architecture d’Aujourd’hui 205, 1979, p. 8 B 2.14 Alessandra Chemollo, from Acocella, Alfonso, An architecture of place. Rome 1992, p. 96 B 2.15–17  Halfen GmbH & Co. KG B 2.18 – 20  Jaume Avellaneda, Barcelona B 2.21– 22  Alfonso Acocella, Florence B 2.23 Roland Krippner, Munich B 2.24 – 29  Moeding Keramikfassaden GmbH, Marklkofen B 2.30 Verena Herzog-Loibl, Munich B 2.31 Peter Bonfig, Munich B 2.32 Moeding Keramikfassaden GmbH, Marklkofen B 2.33 Roland Krippner, Munich B 2.34 Alfonso Acocella, Florence B 2.35 Werner Lang, Munich B 2.36 Decorated walls of modern architecture. Tokyo 1983, p. 30 B 2.37– 38  Alfonso Acocella, Florence B 2.39 Tectónica 15/2003, p. 21 B 2.40 – 41  Verena Herzog-Loibl, Munich B 2.42 – 43  Tectónica 15/2003, p. 18 B 2.44 Alessandro Ciampi, Florence, from: Acocella, Alfonso, Involucri in cotto. Florence 2002, p. 96 B 2.45 Alessandro Ciampi, Florenz, from: Acocella, ­Alfonso. Involucri in cotto. Florence 2002, p. 98 B 2.46 Alessandro Ciampi, Florence, from: Acocella, Alfonso, Involucri in cotto. Florence 2002, p. 98f. p. 94 Bruno Klomfar, Vienna p. 95 Beat Bühler, Zurich p. 96, 97 Dieter Leistner / ARTUR IMAGES p. 98 Annette Kisling, Berlin / Leipzig p. 99 Andreas Lechtape, Münster p. 100 Klaus Kinold, Munich p. 102, 103  Roland Halbe, Stuttgart p. 104, 105  Timothy Hursley / Moeding Keramikfassaden GmbH, Marklkofen Concrete B 3.1 Thomas Herzog, Munich B 3.2 Klaus Kinold, Munich B 3.3 Verlag Bau + Technik, Düsseldorf B 3.4 BTU Cottbus, Lehrstuhl Entwerfen – Bauen im Bestand (pub.): Architekt Bernhard Hermkes. Cottbus 2003 B 3.6 Sweeney, Robert L., foreword by David G. ­DeLong, Wright in Hollywood, photograph of the John Storer House, p. 109, ©1994 MIT / Architectural History Foundation, by permission of The MIT Press, Cambridge B 3.7 Klaus Kinold, Munich B 3.8 Frank Kaltenbach, Munich B 3.9 Grimm, Friedrich, Richarz, Clemens, Hinterlüftete Fassaden. Stuttgart /Zurich 1994, p. 161 B 3.11 DIN 18 500 Parts 1– 3. 1991 B 3.12 InformationsZentrum Beton, Erkrath B 3.13 –16  Heeß, Stefan: Mehr als nur Fassade. Konstruktion von Betonfertigteil- und Betonwerkstein-Fassaden. Wiesbaden B 3.17 Großformatige Fassaden. Fassaden mit Holz­ zement. Published by Eternit AG. Berlin 2001, p. 12 B 3.18 Archive Olgiati B 3.19 –20  Dyckerhoff Weiss Marketing und Vertriebs gesellschaft p. 117 Georg Aerni, Zurich


p. 118, 119  Michael Compensis, Munich p. 120 © Jens Weber, Munich p. 121 Ulrich Schwarz, Berlin p. 122 Christoph Rehbach p. 123 Roland Halbe /ARTUR IMAGES p. 124 Roland Halbe, Stuttgart p. 125 Daniel Malhão, Lisbon p. 126, 127  Christian Richters, Münster p. 128 Brigida González, Stuttgart p. 129 Bruno Klomfar, Vienna Timber B 4.1 Shinkenchiku-sha, Tokyo B 4.2 Sawyer, Peter: The Oxford illustrated history of the Vikings. Oxford 1997, p. 191 B 4.3 Herzog, Thomas et al.: Holzbau Atlas. Munich 2003, p. 26 B 4.4 Edoardo Gellner, Cortina d’Ampezzo B 4.5 Verena Herzog-Loibl, Munich B 4.6 –7 Herzog, Thomas et al.: Holzbau Atlas. Munich 2003, p. 31– 33 B 4.8 Baus, Ursula, Siegele, Klaus, Holzfassaden. Stuttgart / Munich 2001, p. 19 B 4.9 –10 Herzog, Thomas et al., Holzbau Atlas. Munich 2003, p. 34 – 46 B 4.11 Hans-Joachim Heyer, Boris Miklautsch / Werkstatt für Photo­graphie, University of Stuttgart B 4.12 Friedemann Zeitler, Penzberg B 4.13 Hans-Joachim Heyer, Boris Miklautsch / Werkstatt für Photo­graphie, University of Stuttgart B 4.14 Herzog, Thomas et al., Holzbau Atlas. Munich, 2003, p. 43 B 4.15 Hans-Joachim Heyer, Boris Miklautsch / Werkstatt für Photo­graphie, University of Stuttgart B 4.16 Herzog, Thomas et al., Holzbau Atlas. Munich, 2003, p. 40 B 4.17 Hans-Joachim Heyer, Boris Miklautsch / Werkstatt für Photo­graphie, University of Stuttgart B 4.18 Strandex Europe, Walmley B 4.19 Christian Cerliani, Zurich B 4.20 Ruedi Walti, Basel B 4.21 Jonathan Levi, Boston B 4.22 – 23  Christian Richters, Münster B 4.24 Eduard Hueber, New York B 4.25 Dieter Leistner /ARTUR IMAGES B 4.26 Frank Kaltenbach, Munich B 4.27 Annegret Rieger, Munich B 4.28 Heike Werner, Munich B 4.29 Friedrich Busam /architekturphoto, Düsseldorf B 4.30 Reto Führer, Felsberg B 4.31 Christian Richters, Münster B 4.32 – 34  Sampo Widmann, Munich B 4.35 – 41  Informationsdienst Holz, Düsseldorf 1992 B 4.42 Verena Herzog-Loibl, Munich B 4.43 Werner Huthmacher /ARTUR IMAGES B 4.44 Frank Kaltenbach, Munich B 4.45 Roland Schweitzer, Paris B 4.46 Roland Halbe, Stuttgart B 4.47 Roland Schweitzer, Paris B 4.48 – 49  Theo Ott Holzschindeln GmbH, Ainring B 4.50 Gerhard Hagen, Bamberg B 4.51 Stefan Müller-Naumann, Munich B 4.52 Satoshi Asakawa, Tokyo B 4.53 Hans-Georg Esch, Hennef p. 142 top:  Michael Freeman, London p. 142 bottom:  Sampo Widmann, Munich p. 144, 145  Christian Richters, Münster p. 146 Heinrich Helfenstein, Adliswil p. 147 Shinkenchiku-sha, Tokyo p. 148 Peter Bonfig, Munich p. 149 Henning Koepke, Munich p. 150 Christian Richters, Münster p. 151 Dietmar Strauß, Besigheim p. 152 Marko Huttunen, Helsinki p. 153 Daniel Malhão, Lisbon p. 154 Dieter Leistner /ARTUR IMAGES p. 157 Büro Kaufmann, Dornbirn Metal B 5.1 Jo Reid & John Peck, Newport B 5.2 N. P. Goulandris Foundation, Museum of ­Cycladic Art, Athens


B 5.3 Münchener Stadtmuseum, Munich B 5.4 John Gay, London, from, Murray, John (pub.): Cast Iron. London 1985, p. 28 B 5.5 The Estate of R. Buckminster Fuller, Santa Barbara B 5.6 Erika Sulzer-Kleinemeier, Gleisweiler B 5.7 Ardean Miller, New York, from Airstream – The history of the land yacht. San Francisco, p. 69 B 5.9 –10  Jo Reid & John Peck, Newport B 5.11 Jan Cremers, Munich B 5.12 Verena Herzog-Loibl, Munich B 5.13 Jan Cremers, Munich B 5.14 Verena Herzog-Loibl, Munich B 5.15 Jan Cremers, Munich B 5.16 Dennis Gilbert / VIEW /ARTUR IMAGES B 5.17 Jan Cremers, Munich B 5.21 Hoesch Siegerlandwerke GmbH; Siegen B 5.22 Alcan Singen GmbH; Singen B 5.24 Photos: Frank Kaltenbach, Munich B 5.25 Peter Cook / VIEW /ARTUR IMAGES B 5.27 Heinrich Fiedler GmbH & Co. KG; Regensburg B 5.28 – 32  Mevaco GmbH; Schlierbach B 5.33 – 34  Alcan Singen GmbH; Singen B 5.35 Heike Werner, Munich B 5.36 – 37  Heinrich Fiedler GmbH & Co. KG; Regensburg B 1.5.38 – 39  Heike Werner, Munich B 1.5.40 Frank Kaltenbach, Munich B 1.5.41 Heinrich Fiedler GmbH & Co. KG; Regensburg B 1.5.42 AIM; Nürtingen B 1.5.44, 46  From Kaltenbach, Frank (pub.): Transluzente Materialien. Glas, Kunststoff, ­Metall. Detail Praxis. Munich, 2003, p. 98 B 1.5.47 Heike Werner, Munich B 1.5.48 F. Carl Schröter, Hamburg B 1.5.49 – 50  Heike Werner, Munich B 1.5.51 Hauer und Boecker; Oelde B 1.5.52 Heike Werner, Munich B 1.5.53 – 54  Gebr. Kufferath GmbH & Co. KG; Düren p. 172, 173  Dieter Lechner, Munich p. 174, 175  Bernhard Moosbrugger, Zurich p. 176 John Donat, London p. 177 left:  Werner Lang, Munich p. 177 right:  Ken Kirkwood, Desborough p. 178, 179  Stefan Müller, Berlin p. 180 Werner Huthmacher, Berlin p. 181 Cree GmbH p. 182 Paul Warchol, New York p. 183 Christian Richters, Münster p. 184 Heinrich Helfenstein, Zurich p. 185 Klemens Ortmeyer /architekturphoto, Düsseldorf p. 186, 187  Hélène Binet, London Glass B 6.1 Dennis Gilbert / VIEW/ARTUR IMAGES B 6.2 Achim Bednorz, Cologne B 6.3 Daidalos 66/1997, p. 85 B 6.5 Georges Fessy, Paris B 6.6 Werner Lang, Munich B 6.7– 9 Schittich, Christian et al.: Glasbau Atlas. ­Munich / Basel 1998 B 6.11 Roderick Coyne, London B 6.12 Hans-Georg Esch, Hennef B 6.13 Georges Fessy, Paris B 6.14 Christian Schittich, Munich B 6.15 Schittich, Christian et al.: Glasbau Atlas. ­Munich / Basel 1998, p. 90 B 6.16 –17  Herzog, Thomas: Sonderthemen Baukonstruktion. Materialspezifische ­Technologie und ­Konstruktion – Gläser, Häute und Membranen. Munich 1998, p. 11 (unpublished) B 6.18 – 20  Schittich, Christian et al., Glasbau Atlas. ­ Munich / Basel 1998 B 6.21 Klaus Littmann, https://de.wikipedia.org/wiki/ Gro%C3%9Fer_Garten_(Hannover)#/media/ File:Glasfoyer_im_Gro%C3%9Fen_Garten.jpg, CC BY-SA 3.0 B 6.22 Herzog, Thomas: Sonderthemen Bau­

konstruktion. Materialspezifische Technologie und Konstruktion – Gläser, Häute und Membranen. Munich 1998, p. 36 (unpublished) B 6.23 Schittich, Christian et al.: Glasbau Atlas. ­Munich / Basel 1998, p. 120 B 6.24 – 25  Kaltenbach, Frank (pub.): Transluzente Materialien. Munich 2003 B 6.26 – 28  Schittich, Christian et al.: Glasbau Atlas. Munich / Basel 1998 B 6.29 David Sundberg, New York p. 198 Nigel Young, Surrey p. 199 Duccio Malagamba, Barcelona p. 200, 201 top:  Florian Holzherr, Munich p. 201 bottom:  Christian Richters, Münster p. 202 top left:  Kim Yong Kwan, Seoul p. 202 top right, bottom:  Timothy Hursley, Little Rock p. 203 Kim Yong Kwan, Seoul p. 204 top:  Christian Schittich, Munich p. 204 middle:  Herzog & de Meuron, Basel p. 204 bottom:  Maxim Schulz, Hamburg p. 205 Herzog & de Meuron, Basel p. 206 top:  Dennis Gilbert / VIEW /ARTUR IMAGES p. 206 bottom:  John Linden, Woodland Hills p. 207 Jörg Hempel, Aachen p. 208 Michel Denancé, Paris p. 209 Christian Schittich, Munich p. 210 Hans Ege, Waggis p. 211 John Linden, Woodland Hills p. 212, 213  Jocelyne van den Bossche, London p. 214, 215  Dennis Gilbert / VIEW /ARTUR IMAGES Plastics B 7.1 Simon Burt /APEX, Exminster B 7.2 Hans Hansen / Vitra, Hamburg B 7.3 The MIT Museum, from Hess, Alan, Googie: ­Fifties Coffee Shop Architecture. San Francisco 1986, p. 50 B 7.4 – 5 Centraal Museum, Utrecht B 7.6 Buckminster Fuller Institute, Los Angeles B 7.7 Frei Otto, Warmbronn B 7.8 Richard Einzig /Arcaid, Kingston upon Thames B 7.10 Christian Kandzia, Stuttgart B 7.12 Werner Lang, Munich B 7.13 Tohru Waki / Shokokusha, Tokyo B 7.14 –16  Kaltenbach, Frank (pub.): Transluzente Materialien. Munich, 2003 B 7.17 Hufton + Grow, Hertford B 7.18 – 21  Detail 06/2000, p. 1,048 –1,054 B 7.22 Ingmar Kurth, Frankfurt p. 224 Stefan Müller-Naumann, Munich p. 225 Wolfram Janzer /ARTUR IMAGES p. 226 Christian Richter, Münster p. 227 Bleda + Rosa, Valencia ps. 228, 229  Philippe Ruault, Nantes p. 230 Adam Mork, Copenhagen p. 231 Werner Lang, Munich p. 232 Verena Herzog-Loibl, Munich p. 233 Allianz Arena, Munich ps. 234, 235  Skyspan (Europe) GmbH, Rimsting

Part C

p. 236 Thomas Herzog, Munich Multilayer glass facades C 1.1 Zooey Braun /ARTUR IMAGES C 1.2 Werner Lang, Munich C 1.5 Werner Lang, Munich C 1.7 Waltraud Krase, Frankfurt C 1.8 Richard Schenkirz, Leonberg C 1.11 Rudi Graf, Munich C 1.15 Richard Bryant, Kingston upon Thames C 1.18 –19  Werner Lang, Munich C 1.22 – 23  Werner Lang, Munich C 1.26 Hans-Georg Esch, Hennef C 1.27 Jürgen Schmidt, Cologne p. 247 top:  Achim Bednorz, Cologne p. 247 bottom:  Werner Lang, Munich p. 248, 249 unten:  Roland Halbe /ARTUR IMAGES p. 250 Christian Richters, Münster p. 251 Stefan Müller-Naumann, Munich ps. 252, 253 Jörg Hempel, Aachen

p. 254 top:  Dieter Leistner /ARTUR IMAGES p. 254 bottom:  Thomas Riehle /ARTUR IMAGES p. 255 Thomas Riehle /ARTUR IMAGES ps. 256, 257  Dieter Leistner /ARTUR IMAGES p. 258, 259  Holger Knauf, Düsseldorf p. 260 Ralf Richter, Düsseldorf p. 261 top:  Christian Kandzia, Esslingen p. 261 middle:  Ralf Richter, Düsseldorf p. 261 bottom:  Martin Schodder, Stuttgart p. 262 Duccio Malagamba, Barcelona p. 263 Roland Halbe /ARTUR IMAGES p. 264 Frédéric Druot, Paris p. 265 Torben Eskerod, Copenhagen Manipulators C 2.1 Jean-Marie Hellwig / Prouvé-Archiv Peter Sulzer, Gleisweiler C 2.3 – 4 Verena Herzog-Loibl, Munich C 2.5 Klaus Zwerger, Vienna C 2.6 Verena Herzog-Loibl, Munich C 2.7 ISOTEG Final report. TU Munich, Chair for Building Technologies. Munich 2001 ­(unpublished) C 2.8 Werner Lang, Munich C 2.9 Margherita Spiluttini, Vienna C 2.10 Verena Herzog-Loibl, Munich C 2.11 Hans Werlemann, Rotterdam C 2.12 Michael Heinrich, Munich C 2.13 Christian Gahl, Berlin C 2.14 Roland Halbe /ARTUR IMAGES C 2.15 Eduard Hueber, New York C 2.16 Margherita Spiluttini, Vienna C 2.17 Christian Richters, Münster C 2.18 Moritz Korn C 2.19 Dominic Büttner, Zurich C 2.20 Klaus Kinold, Munich C 2.21 Shinkenchiku-sha, Tokyo C 2.23 Satoshi Asakawa, Tokyo C 2.24 Constantin Beyer, Weimar C 2.25 Ralph Feiner, Malans C 2.26 Hans-Peter Wörndl, Vienna C 2.27 Ritchie Müller, Munich C 2.28 Daniel Westenberger, Munich C 2.29 Andreas Gabriel, Munich C 2.30 René Furer, Benglen C 2.31 Thomas Lenzen, Munich C 2.32 Earl Carter, St. Kilda p. 274 Therese Beyeler, Bern p. 275 Tomio Ohashi, Tokyo ps. 276, 277 bottom:  Hisao Suzuki, Barcelona p. 277 top:  Georges Fessy, Paris p. 278 Ingrid Voth-Amslinger, Munich p. 279 Michael Heinrich, Munich ps. 280, 281  Günter Wett, Innsbruck p. 282 Christian Richters, Münster p. 283 Lukas Roth, Cologne p. 284 Eduard Hueber, New York p. 285 top:  Jan Bitter, Berlin p. 285 bottom:  Annette Kisling, Berlin p. 286 Kees Hummel, Amsterdam p. 287 top  Dietmar Strauß, Besigheim p. 288 Shinkenchiku-sha, Tokyo p. 289 Hiroyuki Hirai, Tokyo p. 290 Robertino Nikolic, Wiesbaden p. 291 top:  Robertino Nikolic, Wiesbaden p. 291 bottom:  Thomas Ott, Mühltal p. 292 Richie Müller, Munich p. 293 top:  Sergio Padura, Hecho p. 293 bottom:  Paul Riddle / VIEW /ARTUR IMAGES Solar energy C 3.1 Verena Herzog-Loibl, Munich C 3.4 – 5 Verena Herzog-Loibl, Munich C 3.6 Akademie der Künste, Berlin, Martin-WagnerSammlung, No. 11 F.30a / Photographer: Arthur Köster. VG Bild-Kunst 2020 C 3.7 Robert Krier C 3.8 – 9 TWD Eigenschaften und Funktionen. Info-Mappe 2 des Fachverbands TWD. ­Gundelfingen 2000, p. 5 C 3.10 –11  Roland Krippner, Munich C 3.12 Dieter Leistner /ARTUR IMAGES C 3.13 Viessmannwerke, Allendorf

C 3.14 Viessmannwerke, Allendorf C 3.15 Schott Glas, Mainz C 3.17 Bernd Thissen / Energie Solaire S.A., Sierre C 3.18 Heiko Hellwig, Stuttgart C 3.20 Schittich, Christian (pub.): Gebäudehüllen. Munich, 2001, p. 53 C 3.21 Roland Krippner, Munich C 3.22 Team Rooftop, Berlin C 3.23 Jan-Oliver Kunze, Berlin C 3.24 Jochen Helle, Dortmund C 3.25 – 26  Jakob Schoof, Munich C 3.27 Jens Passoth, Berlin p. 304 Stefan Müller-Naumann, Munich p. 305 Ruedi Walti, Basel p. 306 Nick Brändli, Zurich p. 307 Dieter Leistner /ARTUR IMAGES p. 308 Willi Kracher, Zurich p. 309 Margherita Spiluttini, Vienna ps. 310, 311  Roland Halbe /ARTUR IMAGES p. 312 Jens Willebrand, Cologne p. 313 Jordi Miralles, Barcelona p. 314 top:  Christian Richters, Münster p. 314 bottom:  Entwicklungsgesellschaft Akademie Mont-Cenis mbH, Herne p. 316 Arnold Brunner, Freiburg p. 317 Eibe Sönnecken, Darmstadt p. 318 Verena Herzog-Loibl, Munich p. 319 top: Frank Kaltenbach, Munich bottom: FG+SG fotografia de arquitectura, ­Lisbon p. 320 top: Holger Groß, Berlin bottom: Hans-Georg Esch, Hennef p. 321 Christian Richters, Münster

The authors and publisher would like to thank the following people, manufacturers and companies for providing information and / or drawings: Barbara Finke, Berlin (DE) Böhmer Natursteinbau GmbH, Leutenbach (DE) Cordelia Denks, Munich (DE) Dach + Wand Wolf GmbH & Co. KG, Dornbirn (AT) Delzer Kybernetik GmbH, Lörrach (DE) F. Brüderlin Söhne GmbH, Schopfheim (DE) Götz GmbH, Würzburg (DE) Halfen GmbH & Co. KG, Langenfeld (DE) Hightex Group, Rimsting (DE) Jörg Eschwey, ESO Chile (CL) Josef Gartner GmbH, Gundelfingen (DE) Lavis Stahlbau GmbH, Offenbach (DE) Magnus Müller GmbH, Butzbach (DE) Metallbau A. Sauritschnig GmbH, St. Veit / Glan (AT) MEW Manfroni Engineering Workshop, Bologna (IT) Moeding Keramikfassaden GmbH, Marklkofen (DE) nbk Keramik GmbH & Co., Emmerich (DE) NMP Naturstein Montage GmbH & Co. KG, Vienna (AT) Serge Lochu, Cosylva Paris-Ouest (FR) Stahlbau Wörsching GmbH & Co. KG, Starnberg (DE) Wortmann Projektbau GmbH, Wenden (DE)

Integrated facades C 4.1 Reiner Rehfeld, Düsseldorf C 4.2 Jan Cremers, Munich C 4.3 Verena Herzog-Loibl, Munich C 4.4 www.top-air.it C 4.5 www.trox.de C 4.6 Fraunhofer-in-Haus-Zentrum, Duisburg C 4.7 Thomas Ott, Mühltal C 4.8 Constantin Meyer, Cologne C 4.9 Andrea Helbing, Zurich C 4.10 Maximilian Meisse, Berlin C 4.11 Fraunhofer-inHaus-Zentrum, Duisburg C 4.12 Thomas Jantscher, Colombier C 4.13 Rainer Viertlböck, Gauting C 4.14 Daniel Reisch, Augsburg C 4.15 Daniel Reisch, Augsburg Refurbishing existing facades C 5.1 Archiv Ruinelli Associati, Soglio C 5.2 Fraunhofer IBP C 5.3 Stefan Müller-Naumann, Munich C 5.4 Elias Hassos, Munich C 5.5 © Jens Weber, Munich C 5.10 Ester Havlová, Prague C 5.11 Hannes Henz, Zurich C 5.12 Phillip Vile, London C 5.13 Andrea Martiradonna, Milan C 5.14 Thomas Riehle /ARTUR IMAGES C 5.15 Jakob Schoof, Munich C 5.16 Michael Kiechle-Pausch / IMAGE FOR YOU, Mauerstetten C 5.17 Tomaz Greoric, Ljubljana Green facades C 6.3 Roland Krippner, Munich C 6.4 Roland Krippner, Munich C 6.5 Roland Krippner, Munich C 6.6 Nicole Pfoser, Darmstadt, from Köhler, Manfred (pub.): Handbuch Bauwerks­ begrünung. Cologne 2012, p.109 C 6.7 Paul Raftery C 6.8 Werner Lang, Munich C 6.9 Roland Krippner, Munich C 6.10 Adria Goula, Barcelona C 6.11 Luuk Kramer, Amsterdam C 6.12 Christian Richters, Münster C 6.14 Fink + Jocher, Munich